[HN Gopher] Exploiting vulnerabilities in Cellebrite UFED and Ph...
       ___________________________________________________________________
        
       Exploiting vulnerabilities in Cellebrite UFED and Physical Analyzer
        
       Author : derekerdmann
       Score  : 1771 points
       Date   : 2021-04-21 16:29 UTC (1 days ago)
        
 (HTM) web link (signal.org)
 (TXT) w3m dump (signal.org)
        
       | [deleted]
        
       | systemvoltage wrote:
       | > By a truly unbelievable coincidence, I was recently out for a
       | walk when I saw a small package fall off a truck ahead of me. As
       | I got closer, the dull enterprise typeface slowly came into
       | focus: Cellebrite. Inside, we found the latest versions of the
       | Cellebrite software, a hardware dongle designed to prevent piracy
       | (tells you something about their customers I guess!), and a
       | bizarrely large number of cable adapters.
       | 
       | Does anyone find a package dropping off a truck and first take a
       | picture of it, pick it up and go home to open it?
       | 
       | Even if someone picks up the package, usually taking a picture of
       | it doesn't come to their mind. It's an unsual bit in the story.
       | Unless, they went back and put the bag on the road to show that
       | it was found just for the sake of "recreating the story"
       | purposes.
       | 
       | How does something like a small briefcase just "fall from a
       | truck"? By what mechanism? Briefcase would be stored inside the
       | cabin.
       | 
       | If you're the author, can you explain my suspicion?
        
         | frabjoused wrote:
         | It's a joke.
        
           | systemvoltage wrote:
           | Sorry, please go ahead and downvote my comment so its not
           | cluttering up :)
        
         | bodhi wrote:
         | Its a loquacious take on "fell off the back of a truck".
        
         | matteotom wrote:
         | "Fell off the back of a truck" is usually a metaphor for either
         | stolen or otherwise acquired in a way they don't want to
         | explain.
        
           | systemvoltage wrote:
           | Thanks, I didn't catch this.
        
         | LegitShady wrote:
         | plausible deniability
        
       | sitzkrieg wrote:
       | i find it remarkably unbelievable someone would put a cellebrite
       | bag in the back of a truck given the price alone.. and the timing
       | too. sure
        
         | NullPrefix wrote:
         | I bet the tool was bought from a supplier but Signal team can't
         | disclose it because source protection.
        
           | novok wrote:
           | With all the recent BLM protests going on, I wouldn't be
           | surprised if it was acquired by an activist, even an activist
           | who works in the police force!
        
             | op00to wrote:
             | This is irresponsible and inflammatory. Has nothing to do
             | with the discussion. Please stop.
        
         | marcopet wrote:
         | "fell off the back of a truck" is an idiom [1]. It's not meant
         | literally.
         | 
         | [1] https://www.phrases.org.uk/meanings/fell-off-the-back-of-
         | a-t...
        
           | supergirl wrote:
           | they actually put it a photo of it on the street too
        
           | ampdepolymerase wrote:
           | It's like "a little bird told me".
        
             | myself248 wrote:
             | The "parallel construction" of the civilian world.
        
           | sitzkrieg wrote:
           | oh ok thats a new one for me obviously, but the street photo
           | got me. lol
        
         | spoonjim wrote:
         | "Fell off the back of a truck" is slang for "obtained through
         | illicit means." It comes from the excuse that criminals used to
         | give when caught with stolen property: I didn't steal it, it
         | just fell off a truck.
        
           | sitzkrieg wrote:
           | thank you for clarifying, english is not my main language and
           | that was taken at face value. The going on a walk and picture
           | was too good
        
       | sathackr wrote:
       | Cellebrite's initial response[1] includes this gem
       | 
       | "We have strict licensing policies that govern how customers are
       | permitted to use our technology and do not sell to countries
       | under sanction by the US, Israel or the broader international
       | community."
       | 
       | And these policies are obviously quite effective at preventing
       | such uses.
       | 
       | [1] https://www.theregister.com/2021/04/21/signal_cellebrite/
        
         | FridayoLeary wrote:
         | ah. Those must also be modules that fell from the truck....
         | (these companies clearly have trucks like sieves) I have no
         | doubt that already, cellebrite are on the phone ordering more
         | secure, err 'trucks'
        
       | motohagiography wrote:
       | Wow, that video made my day. This bit is key:
       | 
       | > "For example, by including a specially formatted but otherwise
       | innocuous file in an app on a device that is then scanned by
       | Cellebrite, it's possible to execute code that modifies not just
       | the Cellebrite report being created in that scan, but also all
       | previous and future generated Cellebrite reports from all
       | previously scanned devices and all future scanned devices in any
       | arbitrary way (inserting or removing text, email, photos,
       | contacts, files, or any other data), with no detectable timestamp
       | changes or checksum failures. This could even be done at random,
       | and would seriously call the data integrity of Cellebrite's
       | reports into question."
       | 
       | They've may have just got a lot evidence collected using
       | Cellebrite from phones with (or without) Signal installed on them
       | thrown out of court.
       | 
       | I don't recall the details, but there was an absolute
       | unsubstantiated speculative and surely fictional rumor of at
       | least one entirely theoretical zero-day non-gif formatted image
       | file that exploited a similar class of vulnerability in what was
       | probably not a market leading tool used tangentially for the same
       | purposes, floating around well over a decade ago as well.
       | 
       | I for one am very glad that these hypothetical issues have almost
       | surely been fixed.
        
         | ZeroCool2u wrote:
         | The video made my inner child feel truly vindicated with my
         | choice of username.
        
           | kstrauser wrote:
           | I'm envious.
        
             | kstrauser wrote:
             | ...of your awesome username. I wasn't being snarky!
        
           | doctor_eval wrote:
           | Mwahahahaaa!
        
           | acidburnNSA wrote:
           | Same here.
        
             | HackTheGibson wrote:
             | Same.
        
               | hprotagonist wrote:
               | well, close enough for me.
        
               | mindcrime wrote:
               | /u/hprotagonist - I've always thought you had the best
               | username on HN, for what it's worth!
        
               | hprotagonist wrote:
               | i'm consistently amazed it was available.
        
         | [deleted]
        
       | marcodiego wrote:
       | > One way to think about Cellebrite's products is that if someone
       | is physically holding your unlocked device in their hands, they
       | could open whatever apps they would like and take screenshots of
       | everything in them to save and go over later. Cellebrite
       | essentially automates that process for someone holding your
       | device in their hands.
       | 
       | Aren't Cellebrite products/services more advanced than that? I
       | mean don't they use publicly unknown zerodays to extract data
       | from locked phones?
        
         | [deleted]
        
         | sodality2 wrote:
         | They are more advanced typically than just extracting data from
         | a phone. Not sure to which extent they advertise it brazenly
         | though. Fairly certain they blog about it a lot
        
           | carstenhag wrote:
           | the cellebrite ambassador we talked to (as private company)
           | basically bragged they were the ones that unlocked the San
           | Bernadirno iPhone. I'm sure towards government officials and
           | Law Enforcement they brag even more.
        
             | saagarjha wrote:
             | But they weren't, that was Azimuth: https://www.washingtonp
             | ost.com/technology/2021/04/14/azimuth...
        
               | carstenhag wrote:
               | Hm, interesting. So there are articles saying it's
               | Cellebrite https://www.reuters.com/article/us-apple-
               | encryption-cellebri..., then others saying it was
               | unmentioned professional hackers and then your article
               | where all three possibilities are mentioned.
        
             | sodality2 wrote:
             | Yeah, that wasn't them... so whoever that was lied
        
         | saagarjha wrote:
         | AFAIK there are various "levels" of Cellebrite's products, from
         | "I'm a phone shop and I want something help me make a phone
         | backup so I can restore it" all the way to "tools to break into
         | locked iPhones".
        
       | mot0man wrote:
       | "Fell off a truck"
       | 
       | for those who don't get that it was a joke, the software is
       | available for download on some non legal channels, you just need
       | to look. He doesn't want to reveal the origin.
        
       | amluto wrote:
       | Now if only I could use legitimate tools to access _my own_
       | Signal data on an iOS device.
        
         | NullPrefix wrote:
         | Have you tried going out for a walk and looking for trucks with
         | small packages falling off?
        
         | gruez wrote:
         | doesn't an itunes backup contain all the app data?
        
           | amluto wrote:
           | Not obviously for Signal
        
           | mike_d wrote:
           | I own a Cellebrite, and yeah you are right. The Cellebrite
           | box is nothing other than a phone backup tool. The nice thing
           | it does is implement every backup sync protocol for every
           | version of every mobile OS so you don't have to spend a whole
           | day trying different combinations of iTunes and such.
           | 
           | The "Physical Analyzer" is just a forensics tool. There are
           | dozens of competitors out there that will take a phone and
           | surface the things that might be interesting in a court case
           | or law enforcement investigation.
           | 
           | The product Signal didn't talk about - which I think is the
           | one they are upset about - is Cellebrite Premium. That is
           | their service where law enforcement can send locked or
           | damaged devices to their lab and get back a an image to load
           | into PE. However in 99% of cases devices are either accessed
           | because they are running old software with public
           | vulnerabilities, or using the magic phrase "would you mind
           | unlocking your phone so we can clear this matter up?"
        
             | zerd wrote:
             | I tried to use adb backup to backup my Chrome history/tabs,
             | but it's empty because it has android:allowBackup=false. So
             | unless they're also rooting the phone (which usually wipes
             | the data) or have some 0-day privilege escalations, some
             | apps can't be backed up this way.
        
       | paddlesteamer wrote:
       | > In completely unrelated news, upcoming versions of Signal will
       | be periodically fetching files to place in app storage. These
       | files are never used for anything inside Signal and never
       | interact with Signal software or data, but they look nice, and
       | aesthetics are important in software.
       | 
       | I wish I could see those files in action...
        
         | barbazoo wrote:
         | I don't get it, can anyone elaborate on what they are talking
         | about there?
        
           | rodgerd wrote:
           | Signal is going to start attacking third-party tools once
           | it's installed on your phone.
           | 
           | It's as though Theo decided that OpenSSH should respond to
           | portscanners by trying to pwn the source systems.
        
             | spoonjim wrote:
             | And why shouldn't OpenSSH do that?
        
               | rodgerd wrote:
               | Because I have zero interest in running attack software.
        
             | oh_sigh wrote:
             | No, because that would be active retaliation.
             | 
             | More realistically it is like dropping a file on your
             | private file server
             | DONT_RUN_THIS_BLOWS_UP_YOUR_COMPUTER.exe. You never run it,
             | but maybe somebody exploits your file server, gets all your
             | files, and automatically runs them?
             | 
             | Oh well.
        
               | PeterisP wrote:
               | It really is like dropping a file on your private file
               | server DONT_RUN_THIS_BLOWS_UP_YOUR_COMPUTER.exe - but
               | contrary to your expectations, it's not "oh well", if you
               | placed it there with the intent to trap someone who you
               | expect to be looking at your computer, you may well be
               | liable if their computer blows up, there's no significant
               | difference from active retaliation - the consequences are
               | there, the intent is there, the act is there, it's pretty
               | much the same.
               | 
               | Of course, if some criminal exploits your file server,
               | they are not likely to press charges, but if it triggers
               | on law enforcement who have a warrant to scan your
               | fileserver, that's a different issue.
               | 
               | You'd be just as liable as for physical boobytraps on
               | your property, with pretty much the same reasoning.
        
               | chordalkeyboard wrote:
               | > if you placed it there with the intent to trap someone
               | who you expect to be looking at your computer, you may
               | well be liable if their computer blows up
               | 
               | Liable for what? You haven't promised that the code is
               | safe, and they chose to run it.
               | 
               | > there's no significant difference from active
               | retaliation
               | 
               | There is a significant difference, in active retaliation
               | you choose to attack someone elseks computer, with a trap
               | file the attacker chooses to run files they have stolen
               | from you. Big difference.
               | 
               | > You'd be just as liable as for physical boobytraps on
               | your property, with pretty much the same reasoning.
               | 
               | The reasoning is different, lethal or injurious man traps
               | are prohibited because you don't respond to trespassing
               | with lethal force and you don't know who or what may
               | trigger the trap. Man traps that lock the intruder in a
               | room without injuring them are fine, and used in high
               | security installations.
        
               | salawat wrote:
               | The beauty though, is that law enforcement now can't even
               | know before plugging in and scanning a device whether
               | they'll actually be pwned.
               | 
               | They have to use the exploit to figure out if the phone
               | can nuke that hardware's usability in the future or
               | integrity of any locally stored, non-offsited data.
               | 
               | UNLESS Cellebrite can produce publically for a court of
               | law proof that any potential exploit isn't a valid
               | concern, which means spilling implementation details
               | about how the device works.
               | 
               | Nobody can continue to shut up AND maintain the status
               | quo. Either everyone clams, and Signal can sow reasonable
               | doubt without challenge, crippling Cellebrite's value as
               | a forensic tool. Or someone has to open up about the
               | details of their tool, which, like it or not, will speak
               | _very loudly_ about the ways and methods behind these
               | exploits.
               | 
               | The Checkmate is implied, and oh my, is it deafening.
        
           | TheGeminon wrote:
           | They are implying that future versions of Signal will drop
           | random files on your phone that "may or may not" cause damage
           | to Cellebrite systems.
           | 
           | They are basically putting the threat out that if you use
           | Cellebrite on Signal in the future, you might not get the
           | data you expect, and at worst, it may corrupt the
           | report/evidence.
           | 
           | This also brings into question the chain of custody, as an
           | untrusted device being imaged can alter reports of unrelated
           | devices.
        
             | franga2000 wrote:
             | Damn, a chain of custody where the thing in evidence is
             | also part of not only its own chain but also those of other
             | evidence acquired afterwards? I can't imagine what kind of
             | case law exists around that, but I'm sure it's hilarious!
        
               | cosmie wrote:
               | > also those of other evidence acquired afterwards
               | 
               |  _And_ prior extracts on the device.
        
               | elliekelly wrote:
               | Which is what I don't really understand - it seems like
               | Cellebrite could spin this in their favor so law
               | enforcement would need to purchase a new kit for each
               | device?
        
               | [deleted]
        
         | tony101 wrote:
         | I wonder if the intention here is to deter Cellebrite from
         | parsing Signal files? Or to pressure them into fixing their
         | security vulnerabilities?
        
           | kbenson wrote:
           | _Files will only be returned for accounts that have been
           | active installs for some time already, and only
           | probabilistically in low percentages based on phone number
           | sharding. We have a few different versions of files that we
           | think are aesthetically pleasing, and will iterate through
           | those slowly over time._
           | 
           | Pretty sure it's the former, since the above is a way to
           | ensure that Cellebrite can't just gather all implied exploit
           | files and make sure they've got those specific problems all
           | patched. This is, quite literally, an informational attempt
           | at guerilla/asymmetric warfare, where Signal is trying to
           | make engaging with them too costly, while also making a few
           | blows quite a bit above their weight level. Cellebrite now
           | has to decide whether to keep after this adversary that both
           | is hard to pin down, ambushes them, and has shown it can hit
           | them really hard where it matters (credibility, and thus
           | their pocket book).
        
             | Zarathust wrote:
             | This indeed looks like a FUD statement, implying that they
             | can have an infinite amount of potential vulnerabilities.
             | Realistically though, writing parsers that do not yield
             | control of your whole device is not that complex. The
             | people exploiting iOS zero days can certainly do it.
        
               | spoonjim wrote:
               | But it might be easier for Cellebrite to just stop
               | exfiltrating data from Signal. Of course, other apps
               | could discover similar vulnerabilities.
        
               | chopin wrote:
               | That's not enough. With file system permission, Signal
               | could place files anywhere (like prepared gifs in the
               | Pictures folder).
               | 
               | I think this taints any phone having Signal installed.
        
               | da_big_ghey wrote:
               | the signal are capable for finding more exploit with more
               | time. important piece is that exists now a reasonable
               | doubt on data from the celebrite, so it are not so good
               | for evedince.
        
               | kevinmchugh wrote:
               | It's not that hard but neither is shipping patched
               | versions of ffmpeg. This company will have some catching
               | up to do.
        
               | Karunamon wrote:
               | You're not wrong at all, but if they're shipping these
               | garbage ancient versions of ffmpeg, there are likely
               | _oodles_ of other bugs lurking around. And, if Cellebrite
               | acts like most other companies who 've had their awful
               | security exposed, they will fix only this bug and leave
               | everything else.
        
           | hprotagonist wrote:
           | or just flipping them off, which seems OK too.
        
           | alfiedotwtf wrote:
           | Signal should generalise this into a library so that other
           | app vendors can include these perfectly cromulant files
        
             | simonh wrote:
             | That would reveal all the exploits to Cellebrite, which
             | Signal is trying to avoid.
        
             | FridayoLeary wrote:
             | I imagine many brother app vendors, who may or may not
             | maintain good relationships with Signal might possibly have
             | found a usb drive containing the relevant data on the
             | street. (pure speculation, i don't know anything about
             | moxie, but judging by his tone, i wouldn't be shocked)
        
           | jjoonathan wrote:
           | Nah, Cellebrite will panic for a bit at the possibility of
           | facing repercussions but ultimately not commit enough effort
           | to change anything. Cellebrite's counterparties, however,
           | might not be so complacent.
        
         | supergirl wrote:
         | signal wants to pick a fight with a grey company that gets
         | money for cracking apps? not a good idea
        
           | kevinyew wrote:
           | They're already picking a fight with Cellebrite simply by
           | existing, as Signal is antithetical to everything that
           | Cellebrite stands for.
        
             | f1refly wrote:
             | buying a safe != killing the guy thats invading your house
        
               | sterlind wrote:
               | I think this would be more like including exploding dye
               | packs in your bags of money.
        
           | da_big_ghey wrote:
           | one could view make of an e2e encrypt app that is cause
           | problem for polices as "not a good idea" but there must be
           | some person for to do it.
        
       | Ansil849 wrote:
       | I don't understand the seeming incongruity between these two
       | statements:
       | 
       | On the one hand:
       | 
       | > One way to think about Cellebrite's products is that if someone
       | is physically holding your unlocked device in their hands, they
       | could open whatever apps they would like and take screenshots of
       | everything in them to save and go over later. Cellebrite
       | essentially automates that process for someone holding your
       | device in their hands.
       | 
       | But on the other hand:
       | 
       | > We are of course willing to responsibly disclose the specific
       | vulnerabilities we know about to Cellebrite if they do the same
       | for all the vulnerabilities they use in their physical extraction
       | and other services to their respective vendors, now and in the
       | future.
       | 
       | If UFED just copies data from unlocked phones, why would they be
       | using vulnerabilities to do so?
       | 
       | I guess my question is, is Cellebrite capable of copying locked
       | devices, or more to the point - has vulnerabilities to unlock
       | devices without knowing the access PIN?
        
         | dandelany wrote:
         | > is Cellebrite capable of copying locked devices, or more to
         | the point - has vulnerabilities to unlock devices without
         | knowing the access PIN?
         | 
         | Yes, they even brag about it in their marketing materials:
         | https://www.cellebrite.com/en/a-practical-guide-to-checkm8/
         | 
         | That's a public vunerability, it's anyone's guess how many
         | nonpublic ones they're using.
        
         | g_sch wrote:
         | Based on the post, it sounds like there's some data parsing
         | going on (possibly to present the data in a user-friendly
         | way?), and the parsing step uses outdated versions of software
         | (such as ffmpeg) which have well-documented vulnerabilities in
         | them.
        
         | md_ wrote:
         | Cellebrite claims,
         | 
         | "Lawfully access locked devices with ease Bypass pattern,
         | password or PIN locks and overcome encryption challenges
         | quickly on popular Android and iOS devices"
         | 
         | https://www.cellebrite.com/en/ufed/
        
         | chevill wrote:
         | >If UFED just copies data from unlocked phones, why would they
         | be using vulnerabilities to do so?
         | 
         | I think what he meant to say was that if Cellebrite is used on
         | your locked phone it could be the equivalent of a person having
         | your unlocked phone in their hands where they can do whatever
         | they want. Only cellbrite doesn't do look at random things, it
         | grabs everything.
         | 
         | Cellebrite devices are also frequently used by phone carriers
         | to image your old phone and transfer the data to your newly
         | purchased phone, to give you a clearer idea of what they can
         | do.
        
         | supergirl wrote:
         | they could use vulnerabilities to extract more data. probably
         | it's common to do some obfuscation of data which celebrite
         | might have reverse engineered.
        
       | Malp wrote:
       | While this report is entertaining to read, I have to wonder about
       | possible downstream repercussions of the implications within the
       | last paragraph; if you're in police custody or worse and your
       | Signal app contains some 'aesthetically pleasing files' that
       | interfere with the authoritarian software, it's likely going to
       | be your ass on the line for all sorts of charges.
       | 
       | Don't get me wrong, the implication is enough to discredit
       | Cellebrite, but my initial thoughts are that either this bluff
       | gets called, or there's a non-zero risk of someone landing in
       | even hotter water down the line for using Signal. Of course, this
       | assumes that you're not already neck-deep for having encrypted
       | data and upholding your right to privacy.
        
       | chonkywonk wrote:
       | Apple uses Cellebrite devices in its own stores.
        
       | Nextgrid wrote:
       | So I wonder, why disclose this?
       | 
       | This will just prompt Cellebrite to improve its security process
       | and sandbox the entire tool.
       | 
       | If they wanted to destroy the credibility of the tool, using the
       | vulnerabilities to silently tamper with the collected data or
       | even leaking it online would be a much better option and hit them
       | without any warning, not only jeopardizing those cases but
       | forever casting doubt on not just Cellebrite but their competitor
       | tools.
        
         | faitswulff wrote:
         | Signal may have had countermeasures in place long before the
         | blog post, as well.
        
         | godelski wrote:
         | Any court case where Cellebrite's tools have been used are now
         | in jeopardy since the defence can just say that they were
         | hacked by someone else. There's now reasonable doubt that
         | Cellebrite can't be trusted. This damages their reputation with
         | governments too.
        
           | wglb wrote:
           | This is unlikely to be the case, despite the vulnerabilities
           | that are described.
           | 
           | The process of e-discovery is rife with risks of this sort.
           | When you forensically collect data from a random set of
           | devices from a party that may or may not have porn, HIPAA,
           | GDPR, sample viruses, malware, who know what all.
           | 
           | The short version of it even if the inhaling of this data
           | crashes the device, there are mitigations and protections
           | that will allow the evidence to be ultimately produced.
           | 
           | A crash of the windows host in collection will not invalidate
           | the case.
           | 
           | disclosure: ex-CSO of Relativity, leading provider of
           | e-discovery software.
        
             | Zak wrote:
             | The vulnerability claimed here doesn't necessarily _crash_
             | the computer running the software. It runs arbitrary code,
             | and said code is able to modify the data Cellebrite
             | extracts. It is not clear whether it is possible to detect
             | whether data collected in the past is compromised.
             | 
             | There may be mitigations, but without knowing the full
             | details of the exploit, it sounds a lot like reasonable
             | doubt to me. A good lawyer would spin it exactly that way,
             | putting any cases without sufficient corroborating evidence
             | in jeopardy.
        
               | wglb wrote:
               | If the data is off on another server, it seems unlikely
               | that past cases can be compromised.
               | 
               | There are a whole set of rules about challenging
               | evidence, including electronic evidence. Keep in mind
               | that the other side gets a crack at it also. It is
               | unlikely that the whole case would be thrown out because
               | of a corrupted file. Reasonable doubt is not part of the
               | forensic process--this is what a jury needs to consider
               | to render a verdict.
               | 
               | As pointed out elsewhere, many uses of this tool are
               | extrajudicial.
        
               | holtalanm wrote:
               | > If the data is off on another server, it seems unlikely
               | that past cases can be compromised.
               | 
               | That isn't the point being made here. The data could have
               | been compromised at the point of when it was gathered,
               | not any time later.
        
           | tptacek wrote:
           | Not really. The same circumstances exist for almost all
           | digital evidence. Of course, a lot of Cellebrite usage is
           | extrajudicial already.
        
             | godelski wrote:
             | If you're failing some basic security it isn't going to
             | give much confidence.
             | 
             | But also users don't know now if their systems will explode
             | if they try to gather Signal (or other app) data.
        
               | tptacek wrote:
               | The quality of forensics software is extremely low; a
               | similar story was once written about EnCase, and had zero
               | impact on any legal case anywhere.
        
               | wglb wrote:
               | As in https://www.securityweek.com/forensics-tool-flaw-
               | allows-hack...., yet it is used in cases large and small,
               | civil, criminal, federal state.
        
               | tptacek wrote:
               | Matt Blaze did some research on this, and it seems to
               | turn out that when you put an argument like this in front
               | of a judge or jury, ultimately you have to back it up
               | with evidence that it actually happened; it's not enough
               | to say that the potential existed. Which makes sense,
               | because the potential exists for a lot of stuff,
               | including stuff we don't often talk about.
        
               | wglb wrote:
               | I think this post by signal is not much beyond
               | exceedingly well-crafted nerd sniping [edited for claity]
        
               | polar wrote:
               | https://insights.sei.cmu.edu/blog/forensics-software-and-
               | ora... ?
        
         | tptacek wrote:
         | Whether Cellebrite is secure or not has really not much impact
         | on Signal. Shore up Cellebrite's security, don't, either way,
         | pretty much same threat to users. But calling them out like
         | this could force them to placate _their_ customers by spending
         | money on software security --- something they apparently haven
         | 't been doing --- and inflicting costs on your adversary is
         | good praxis.
        
         | po wrote:
         | Sandboxing doesn't fix the problem. The problem isn't the same
         | as a consumer app where you're trying to protect the OS from
         | being rooted. Their problem is they need to protect the
         | integrity of the report it generates because that's the thing
         | that makes them money.
         | 
         |  _edit:_
         | 
         | One thing they could try to do is to sandbox the parser itself
         | to lower attack surface area... but the damage is done here and
         | I really doubt they will win a security tit-for-tat with
         | Signal.
        
         | Zarathust wrote:
         | It seems to be a retaliatory measure against this:
         | 
         | > When Cellebrite announced that they added Signal support to
         | their software, all it really meant was that they had added
         | support to Physical Analyzer for the file formats used by
         | Signal.
         | 
         | Your case is valid about potential judiciary impact, but it
         | would require for Signal to monitor cases involving Cellebrite
         | and step forward to help the defense while unprompted to do so.
         | Furthermore, Cellebrite clients seems to include entities that
         | do not care so much about a fair trial.
        
         | eli wrote:
         | For one thing, it could otherwise waste a lot of time for the
         | poor white hat hacker who tries to figure out why this oddly
         | formatted file suddenly exists in the app data.
         | 
         | And it doesn't destroy the credibility of the tool to silently
         | mess with its data. People have to know it's happening.
        
         | kbenson wrote:
         | > sandbox the entire tool.
         | 
         | Sandboxing doesn't really help. The problem isn't that the tool
         | is used to infect the rest of the system, but that the tool
         | itself is compromised, the reports it generates are
         | compromised, and and past reports may be compromised. Unless
         | you're pushing that data outside the sandbox (which is a hole
         | in the sandbox, and while much more limited might also be an
         | exploit vector or a way to cause problems in the data) it's
         | still fair game if the sandboxed tool is compromised.
         | 
         | There's multiple reasons to disclose it. First, because as
         | another comment noted it attacks the credibility of the
         | company, and credibility is very important for tools used in
         | court.
         | 
         | Second, because their main goal is to protect Signal, not
         | attack Cellebrite. Making Signal a problem to attempt to gather
         | data about will possibly make them just blacklist Signal as an
         | app they gather for. This could be temporary, but since Signal
         | alluded to many exploits and that they have a bunch queued up
         | for the future, it will always be a risk for Cellebrite to
         | attempt to gather info from Signal, so they might just continue
         | to skip it.
        
           | acdha wrote:
           | This is too quick a dismissal: if they sandboxed each
           | extraction tool they'd be more likely to be able to say that
           | a compromised tool did not compromise the entire system or
           | data collected by other tools. This is exactly why programs
           | like browsers, messaging clients, etc. have moved things like
           | media decoders into separate processes, especially since
           | those tools can be sandboxed quite aggressively whereas a
           | monolithic program will use a fair number of different
           | permissions.
        
             | kbenson wrote:
             | Sure, sandboxing all the individual components and not just
             | the whole would help. That's not what was being suggested
             | though, and is a significantly more complex and labor
             | intensive task than even just fixing all the the included
             | libraries to be more recent and not have known exploits
             | (even thought it would pay dividends later). I wasn't
             | dismissing sandboxing as an effective tool, just noting
             | that it's likely not all that effective to put it all in
             | one sandbox as suggested (and since actually fixing all the
             | problems is likely a lot of work, it doesn't negate the
             | effectiveness of the strategy of Signal by providing an
             | easy solution to the problem).
        
         | choppaface wrote:
         | The public disclosure about the Apple DLLs could potentially be
         | used to drag Apple into any legal case between somebody versus
         | Cellebrite. The disclosure needs to be public versus private or
         | under seal or whatever to absolve the Cellebrite counterparty
         | of any liability from reverse engineering. Suddenly Apple is
         | now in potential collusion with Cellebrite. Or maybe not. This
         | public disclosure makes the threat of Discovery a bit less
         | toothless.
         | 
         | IANAL but I could imagine Cellebrite has existing or pending
         | litigation where this disclosure upsets their position.
        
           | supergirl wrote:
           | does cellebrite appear in any legit court cases? from this
           | blog post it sounds like only "authoritarian" regimes use it.
           | i doubt it would appear in any legit case. it's a shady tool.
           | they'll use it to gather info but will not present this info
           | directly in court, instead use it to gather legitimate proof,
           | if needed.
        
             | syntheticcorp wrote:
             | Cellebrite tech is widely used by western authorities (as
             | well as some "authoritarian" regimes)
        
             | sjy wrote:
             | Yes. You'll find many results for the keyword 'cellebrite'
             | on law.justia.com, canlii.org and austlii.edu.au. These
             | free databases are far from comprehensive and most cases
             | won't go on appeal or end up in a legal research database
             | at all, so this is just the tip of the iceberg.
        
           | redleader55 wrote:
           | I think they mention Apple in an attempt to force them to
           | defend their copyright, else they risk losing it.
           | 
           | I assume Apple will choose to file for copyright infringement
           | than risk being accused of collusion and lose the copyright
           | on that iTunes or parts of it.
        
             | seba_dos1 wrote:
             | That's not how copyrights work, you're confusing it with
             | trademarks.
        
               | Gaelan wrote:
               | Right, but Apple now has to choose between suing
               | Cellebrite and (tacitly) condoning their behavior. Not
               | the same as losing the copyright, for sure, but still.
               | 
               | Not clear which the parent was talking about. Maybe both?
        
         | spinny wrote:
         | Probably disclosure is the best option.
         | 
         | Silently tamper with the data might cross a legal line. doing
         | this might put at risk current or past cases where there is a
         | legitimate reason to use this sort of tool.
         | 
         | Privacy can be hard. While i 100% defend everybody has the
         | right to privacy, i can also see the need for the capability to
         | break it. Maybe the answer for this is a very tight regulation
         | around the uses of this kind of hardware/software, but that
         | regulation would have to keep up with the pace of technology
        
           | a-dub wrote:
           | > Privacy can be hard. While i 100% defend everybody has the
           | right to privacy, i can also see the need for the capability
           | to break it. Maybe the answer for this is a very tight
           | regulation around the uses of this kind of hardware/software,
           | but that regulation would have to keep up with the pace of
           | technology
           | 
           | i've always wondered if there could be a cryptographic
           | solution to this. issuing decryption keys to governments
           | seems rife for abuse, but some sort of multi-party situation
           | where governmental and non-governmental entities have to
           | cooperate (with actual multiparty key material) to perform a
           | decryption authorized by warrants- with said non-governmental
           | agencies acting as a check on usage of those warrants, their
           | frequency and the eventual publication of their usage could
           | be an interesting approach.
           | 
           | personally i think strong encryption should be a requirement
           | for digital evidence, but even that can be forged.
           | 
           | strange times we live in.
        
             | toast0 wrote:
             | > i've always wondered if there could be a cryptographic
             | solution to this. issuing decryption keys to governments
             | seems rife for abuse, but some sort of multi-party
             | situation where governmental and non-governmental entities
             | have to cooperate (with actual multiparty key material) to
             | perform a decryption authorized by warrants- with said non-
             | governmental agencies acting as a check on usage of those
             | warrants, their frequency and the eventual publication of
             | their usage could be an interesting approach.
             | 
             | I would be willing to consider a solution where you need to
             | have agreement from the UN Security council (maybe just the
             | permanent members) in order to decrypt whatever you want.
             | If you can get those countries to agree, it's probably
             | important.
        
       | xchip wrote:
       | Any idea what this means? It is at the bottom of the article:
       | 
       | "In completely unrelated news, upcoming versions of Signal will
       | be periodically fetching files to place in app storage. These
       | files are never used for anything inside Signal and never
       | interact with Signal software or data, but they look nice, and
       | aesthetics are important in software.[...]"
        
         | tptacek wrote:
         | They're alluding to the fact that they can randomly pop
         | Cellebrite installations by planting anti-Cellebrite malware on
         | their users phones.
        
       | po wrote:
       | This is truly a hacker's retort.
       | 
       | It attacks Cellebrite's ability to operate by casting doubt on
       | the reports generated by the product that their customers may
       | wish to use in court.
       | 
       | It places them in legal peril from Apple, and removes any cover
       | Apple would have to _not_ take legal action. (I assume someone at
       | Apple knew they were shipping their DLLs?)
       | 
       | It makes a thinly-veiled threat that any random Signal user's
       | data may actively attempt to exploit their software in the future
       | and demonstrates that it's trivial to do so.
       | 
       |  _edited to add a bonus one:_
       | 
       | Publish some data about what they are doing to help create a
       | roadmap for any other app that doesn't want their data to be
       | scanned.
        
         | upofadown wrote:
         | I really seriously doubt that anyone would ever advance the
         | idea that Signal had deliberately framed them by creating false
         | data on their phone. I don't see this as much more than
         | pointing out that Cellebrite has vulnerabilities, just like the
         | ones they exploit.
        
           | zaphar wrote:
           | You wouldn't imply that Signal had framed you. You would
           | imply that someone else had framed you using the same
           | vulnerabilities as Signal has now indicated exists. i.e. You
           | can't trust Cellebrite because it's now known to be trivial
           | to subvert their software. It's also difficult for Cellebrite
           | to prove that there aren't remaining vulnerabilities in their
           | software since Signal didn't disclose the problems they found
           | and won't do so unless Cellebrite discloses the exploits they
           | claim to be using in Signal.
        
             | PeterisP wrote:
             | It depends on the standard of reliability required. A good
             | defence legal team might use this to argue that the phone
             | data wouldn't be sufficient evidence in the actual criminal
             | proceedings, you do need to prove things beyond all
             | reasonable doubt there; however, even with all these
             | caveats it would be sufficient to use that phone data for
             | investigative purposes and as probable cause for getting a
             | warrant for something else, and then use _that_ for the
             | actual conviction.
             | 
             | For example, let's say they extract the Signal message data
             | from your phone. You successfully convince everyone that
             | this data might have been the result of some tampering.
             | However, that doesn't prevent investigators from using that
             | message history to find the other person, and get them to
             | testify against you.
        
               | filmgirlcw wrote:
               | That's not true, at least if we're talking fourth
               | amendment issues in the US. If the evidence was thrown
               | out, any additional information gleaned from that
               | evidence could be thrown out too. And in a scenario like
               | what you described, it likely would.
               | 
               | That's not a guarantee, of course, and it could be
               | possible for police to corroborate that you had contact
               | with someone else in another way (through records from a
               | wireless carrier or by doing shoe leather investigative
               | work) and use try to get data on that person to get them
               | to testify, but if their only link was through messages
               | that had been deemed inadmissible, they can't use that
               | witness.
               | 
               | The more likely question in a scenario you describe would
               | be if the compromised Signal data would be enough to
               | raise questions about the validity of all the data on the
               | device. I.e., if Signal is out, can they use information
               | from WhatsApp or iMessage or whatever. Past case law
               | would suggest that once compromised, all of the evidence
               | from the device is compromised -- but a judge might rule
               | otherwise.
               | 
               | It would be cool if Signal or another app could use those
               | exploits they've uncovered to inject randomized data into
               | the data stores of other messaging applications too. You
               | know. Just as an experiment.
        
               | neodymiumphish wrote:
               | Wrong. You're talking about "fruit of the poisonous
               | tree", which only involves evidence found as a result of
               | an illegal search. A legal search that results in "false"
               | evidence, which is later used to find "real" evidence
               | will still meet sufficiency in court, because the
               | now-"real" evidence is still admissible, just like the
               | "false" evidence is admissible. It's just that the
               | defense can have the "false" evidence thrown out because
               | it's not verifiable.
               | 
               | In the example being discussed here, it's absolutely
               | still fine for LE and there isn't a need to find a
               | secondary source that side-steps the FOTPT argument. In
               | fact, I could drag a subject into an interview, take his
               | phone and present a warrant to search his phone.
               | 
               | If he refuses to unlock the phone, I can say "fine, we'll
               | use our special software instead" and take it back to
               | another room. After the interview, I give him back his
               | phone and immediately bring in his co-conspirator. If I
               | show the conspirator fake messages between him and my
               | first subject and get him to testify against my subject,
               | that's still admissible. If this is the case, why would
               | using potentially-false/unverifiable Cellebrite data be
               | inadmissible?
        
             | upofadown wrote:
             | You can't just claim an unknown entity framed you and hope
             | to get anywhere. Heck, you could just as well claim that
             | Cellebrite themselves had it in for you.
             | 
             | Cellebrite has never claimed any particular exploits in
             | Signal. Signal is exploitable in this particular way for
             | entirely obvious and common reasons.
        
               | rOOb85 wrote:
               | It's about casting doubt on their software and it's
               | trustworthyness.
               | 
               | In computer forensics it's ALL about being able to
               | verify, without a shadow of doubt that something is what
               | they say it is. Chain of custody rules everything. This
               | blasts a huge gaping hole in all that. He's proven that
               | chain of custody can be tampered with and undetected.
               | Files can be planted, altered or erased. Reports can
               | altered. Timestamps can be changed. The host OS can be
               | exploited. It calls all past and future cellbrite reports
               | into question. Cellbrite can no longer guaranty their
               | software acts in a consistent reliable verifiable way. It
               | leaves doubt.
        
               | wglb wrote:
               | > In computer forensics it's ALL about being able to
               | verify, without a shadow of doubt that something is what
               | they say it is
               | 
               | Mostly. The other side gets all the evidence that the
               | opposing side sees. They both get a chance to review it.
               | 
               | > Chain of custody rules everything.
               | 
               | Agree.
               | 
               | > This blasts a huge gaping hole in all that.
               | 
               | Not really. The analysis goes in two steps. One is to
               | pull all the data from the phone, in a chain-of-custody
               | manner. In an adversarial case, both sides can do this.
               | 
               | The collection and analysis go into two steps. First is
               | moving the data to windows box. Next is the analysis. As
               | I understand it, the analysis portion is where things can
               | explode. Then, if in the hands of someone skilled in
               | forensics, the extracted data would be saved in some
               | other device, possibly to be shared with the other side.
               | Then the risky, potentially explosive analysis would be
               | done. It is very unlikely that all previous cases exist
               | on that device and nowhere else.
               | 
               | Therefore,
               | 
               | > It calls all past and future cellbrite reports into
               | question.
               | 
               | is not true, as the extracted files are likely not on the
               | collecting windows device.
               | 
               | In any case, it is not clear how many uses of this device
               | are in actual legal environments.
        
               | adriancr wrote:
               | By mearly backing up phone with cellebrite it may run
               | exploits.
               | 
               | Exploits may fuck up phone, backup and even cellebrite
               | host os.
               | 
               | As such, phone, backed up data and reports are useless
               | going forward.
        
               | hvis wrote:
               | > As I understand it, the analysis portion is where
               | things can explode.
               | 
               | This very blog post says they have found similar
               | vulnerabilities in both steps.
        
               | zaphar wrote:
               | Why would it have to be an unknown entity? I imagine in
               | at least some court cases there could be potential
               | antagonists to pin the blame on.
        
               | novok wrote:
               | You can claim that by having signal on your phone, it
               | probably compromised the evidence gathering and you
               | didn't know about it and you don't know how, so that
               | evidence is not trustworthy. Kind of like police opening
               | anti-tamper / anti-shoplifting seals which ruin the item
               | they are trying to confiscate with a large amount of dye.
        
               | [deleted]
        
               | derivagral wrote:
               | You'd claim that the tooling used and thus the evidence
               | is unreliable. Not because of yourself or anybody
               | targeting yourself, but due to other actors attacking
               | Cellebrite and leaving you as collateral damage. You'd
               | base this on testimony from other (court-authorized)
               | experts, perhaps even the CEO of a major privacy app.
               | Would be an interesting trial to follow in the US, not
               | sure I'd want to be the defendant though.
        
         | polar wrote:
         | Cellebrite acquired BlackBag Technologies recently. BlackBag
         | emerged from Apple's security team.
        
           | gnud wrote:
           | Fitting name.
           | 
           | Black-bag the opposition politican, and then black-bag her
           | phone.
        
           | anakaine wrote:
           | A little different from brown bag, in which the non-traceable
           | payment travels under the table.
        
             | jeffrallen wrote:
             | Or dog shit under a door.
        
         | ASalazarMX wrote:
         | All that trouble becaused a bag conveniently "fell from a
         | truck". All in all I'm really happy for all this.
        
           | jjoonathan wrote:
           | I am happy to see the bag survived its most untimely truck
           | tumble while remaining a e s t h e t i c a l l y - - - p l e
           | a s i n g.
        
             | daemin wrote:
             | What a sturdy bag it is!
        
           | batch12 wrote:
           | I found that funny too. It sounds to me like a good way to
           | end up with the device to analyze without being constrained
           | by a contract or EULA prohibiting it.
        
             | cheschire wrote:
             | Yes, it's known as a euphemism. TFA just took the joke to
             | hilarious extremes with the photos.
             | 
             | https://www.phrases.org.uk/meanings/fell-off-the-back-of-
             | a-t...
        
           | ampdepolymerase wrote:
           | Indeed, how _convenient_. If it truly did fall off the truck
           | right while he is on a walk then there is the possibility
           | that is a rubber duckie attack. This is basically the
           | equivalent of leaving a USB flash drive lying around. I hope
           | the author took the necessary precautions when reverse
           | engineering the device. Companies like cellebrite have deep
           | connections to certain three letter communities that staging
           | this sort of attacks trivial.
        
             | djoldman wrote:
             | I think we can be relatively confident that the connected
             | machine was airgapped and perhaps run in a VM.
             | 
             | Perhaps even in a faraday cage..
        
               | boredpenguin wrote:
               | > (...) and perhaps run in a VM.
               | 
               | One of the screenshots[0] shows the VMware Tools Service
               | running, so yeah, looks like a virtualized guest.
               | 
               | [0]: https://signal.org/blog/images/cellebrite-dlls-
               | loaded.png
        
             | CPLX wrote:
             | > If it truly did fall of the truck
             | 
             | lol
        
               | baby wrote:
               | Seeing reactions like GP's I'm surprised at how many
               | people don't know this expression.
        
               | ASalazarMX wrote:
               | I thought it was an euphemism because they couldn't
               | reveal who gave it to them. Confessing it was stolen,
               | even as an euphemism, is too blatant to be taken
               | seriously IMO.
        
               | bawolff wrote:
               | Even if you didn't, i think its pretty obvious from
               | context.
        
               | f38zf5vdt wrote:
               | If English is your second language, you may not have come
               | across it. It's a very informal and infrequent idiom.
        
               | baby wrote:
               | FWIW we have the exact same expression in French "c'est
               | tombe du camion"
        
               | CloselyChunky wrote:
               | Dito for German: "vom Laster gefallen"
        
             | jacquesm wrote:
             | "falling off a truck" is slang for "was stolen".
        
               | thayne wrote:
               | Given the sort of business Cellebrite is in, they would
               | probably still want to treat anything connected to it
               | with an overabundance of caution.
        
               | ASalazarMX wrote:
               | TIL:
               | https://idioms.thefreedictionary.com/fall+off+a+truck
               | 
               | Edit: looking up a bit more, it seems like this idiom is
               | used to denote goods sold for cheap because they were
               | stolen. Like "Bob is selling genuine iPhones very cheap,
               | I fear they fell from the back of a truck".
               | 
               | Edit edit: I initially took it as "we won't tell how we
               | got this", because I didn't know this idiom, but it seems
               | several people agree with this interpretation. Not
               | necessarily stolen, but obtained from an undisclosed
               | source.
        
               | dkjaudyeqooe wrote:
               | That isn't quite right. Although it's commonly used to
               | describe something that's been stolen, it's more
               | generally used to indicate that the speaker doesn't want
               | to talk about where it came from. That's how it's been
               | used in this article.
        
           | spinny wrote:
           | Yup. Those things have way to "fell from a truck". Another
           | win for the "fell from a truck" gang ;)
        
         | londons_explore wrote:
         | Sadly I suspect the people in law enforcement who make
         | purchasing decisions never read the Signal blog, and therefore
         | all these points will be moot.
        
           | Hnrobert42 wrote:
           | They, and the people who support them, do. Moreover, not all
           | of their users are involved in ethically questionable
           | activity. Many of them are scrupulously following due process
           | to thwart people doing really bad things.
        
           | tgsovlerkhgsel wrote:
           | They don't have to read that.
           | 
           | The defense lawyers have to read it, and the people in law
           | enforcement need to read the cases where judges throw out
           | Cellebrite evidence based on that.
        
             | syshum wrote:
             | The problem with that is the cases would need to get to the
             | discovery stage.
             | 
             | 95% of all criminal cases in the US are Plead out largely
             | because the defendant can not afford competent legal
             | representation
             | 
             | This is why all kinds of questionable investigative tactics
             | are still used even some that have clearly been ruled
             | unconstitutional, they know most of the time it will not
             | matter, they just need to get enough to make an arrest, the
             | system will destroy the person anyway no conviction needed,
             | and most likely the person will plead guilty even if
             | innocent just to make the abuse stop
        
               | z77dj3kl wrote:
               | Do all defendants not have the right to an attorney in
               | criminal cases?
               | 
               | If evidence is obviously (or with high chance)
               | disputable, then it puts pressure even in those cases
               | where the attorney recommends the defendant to eventually
               | plead.
               | 
               | Or maybe the attorneys available to those who can't
               | afford are just crap in general?
        
               | syshum wrote:
               | >>Do all defendants not have the right to an attorney in
               | criminal cases?
               | 
               | In theory yes, but in most cases that will be a
               | overworked lawyer that has 100's or 1000's of other
               | active cases, and will not spend time other than
               | negotiation the best deal.
               | 
               | Even if you happen to get a good public defender that has
               | the ability to devote lots of time to your individual
               | case, they would have no budget to hire an expert witness
               | to present the vulnerabilities in the Cell-bright
               | software to a jury
               | 
               | Your best bet would be if the ACLU or EFF took an
               | interest in your case, but they take on very few cases
               | relatively speaking and tend to focus on precedent
               | setting cases, or cases that have high public interest
               | (or can be made to have high public interest)
               | 
               | >Or maybe the attorneys available to those who can't
               | afford are just crap in general?
               | 
               | In some cases they are incompetent, however in most cases
               | they are just underfunded and massively over worked. In
               | most jurisdictions the public defenders office is funded
               | is 1/10 or less of what the prosecutors office is funded
               | at.
        
             | waltwalther wrote:
             | This.
        
             | nvr219 wrote:
             | The worst enterprises using Cellebrite don't really have to
             | worry about defense lawyers.
        
           | jjoonathan wrote:
           | They won't be moot when defense lawyers bring them up.
        
             | londons_explore wrote:
             | Doesn't matter. When you can go through every message on
             | someones phone back for years, I'm sure you can find
             | something to put nearly anyone in prison for.
             | 
             | No need to tell the court how you found out about the
             | lawnmowing for the neighbour that was never reported to the
             | IRS...
        
               | filmgirlcw wrote:
               | When you can call into question the data integrity of the
               | items on the device and whether the information from that
               | device is accurate or was inserted by the machine used to
               | break into it, that is some very basic fourth amendment
               | stuff that could possibly get all items taken from the
               | device deemed inadmissible.
        
               | neodymiumphish wrote:
               | Eh, this goes two ways. Cellebrite is rarely going to
               | result in the only meaningful evidence that proves a
               | single element of the offense. Instead, it is often used
               | to further an investigation in order to find evidence
               | that is more damning and of a higher evidentiary value.
               | Fortunately for law enforcement, the integrity of the
               | Cellebrite-obtained data is all that important if it
               | leads to further evidence that is more significant.
        
               | kstrauser wrote:
               | I don't think that's true. There's a legal idea of "fruit
               | of the poisonous tree"[0] that basically says you can't
               | use bad evidence, either in court or as an excuse to
               | collect more, valid evidence. The defense attorney would
               | say "if it hadn't been for that completely untrustworthy
               | Cellebrite evidence, the police wouldn't have been able
               | to get that search warrant they used to find the gun at
               | his house, so we want that thrown out." And the judge
               | would probably go along with that, and if they don't an
               | appeals court probably would.
               | 
               | [0] https://www.law.cornell.edu/wex/fruit_of_the_poisonou
               | s_tree
        
               | maweki wrote:
               | Even if parallel construction wouldn't exist, in Germany,
               | for example, illegally obtained evidence is still valid
               | in court.
        
               | chopin wrote:
               | To be more pedantic, evidence derived from illegally
               | obtained evidence may be admissible but afaik the
               | illegally obtained evidence is not.
               | 
               | In the Metzler kidnapping case the first confession was
               | not admissible in court which had been obtained under
               | threat of torture.
        
               | hunter-gatherer wrote:
               | A defense team would need to show that the report had
               | indeed been spoiled with such an exploit as demonstrated
               | by the Signal team. Just because the possibility exists
               | doesn't mean it happened. If there is a significant
               | evidence report from a cellebrite pull, it almost always
               | means that it either successfully unlocked the device or
               | acquired a full physical image or both.
               | 
               | A report doesn't have to be generated by PA. A forensic
               | examiner is free to use other methods to examine the
               | binary. So long as the examiner can explain all the
               | actions and any artifacts that would be left behind.
        
               | neodymiumphish wrote:
               | Correct!
               | 
               | Plus, most law enforcement seizes the device and keeps it
               | until after the trial. If there were valid arguments
               | against the authenticity of data in the extraction
               | report, it would be easy to verify that data's existence
               | by checking the phone, re-extracting the data using a
               | known-clean UFED, etc. This isn't the end of the world by
               | any means for legal mobile device searches.
        
               | kstrauser wrote:
               | Except that if the device is compromised, it could have
               | changed the data on the phone. The phone, as evidence,
               | can't be trusted anymore.
        
               | neodymiumphish wrote:
               | Signal never indicated this in the blog. They said that
               | the phone would have a file that could be used to
               | victimize the UFED PC after the extraction completes.
               | It's plausible that the UFED could be infected post-
               | extraction with malware that re-establishes a connection
               | to the phone to infect it in reverse, but this is
               | extremely unlikely and it would be easy to determine
               | (assuming the UFED still exists and hasn't been
               | meaningfully modified since the extraction.
               | 
               | For the UFED Touch, for example, the device runs the
               | extraction and saved the result to a flash drive or
               | external drive. This is then reviewed with the UFED
               | software on another machine (laptop, desktop, whatever).
               | What you're describing would mean that the extraction
               | takes place (one-way. The Touch requests an ABD or iTunes
               | backup process, phone responds with the backup files).
               | The the malicious file in the backup pops and executes a
               | command that runs software on the phone, thus infecting
               | the phone with false data to cover the tracks and make
               | the data on the report match the device. This is
               | unreasonably complex, and I doubt any judge would accept
               | it as enough to consider the data inadmissible. Let alone
               | the fact that the data likely exists elsewhere in a
               | verifiable way (Facebook Messenger, WhatsApp, Google
               | Drive, etc), which the initial extraction results should
               | give probable cause to the cops to obtain.
        
               | tablespoon wrote:
               | > I don't think that's true. There's a legal idea of
               | "fruit of the poisonous tree"[0] that basically says you
               | can't use bad evidence, either in court or as an excuse
               | to collect more, valid evidence.
               | 
               | I think the police have been using "parallel
               | construction" to get around that for some time.
               | 
               | https://en.wikipedia.org/wiki/Parallel_construction
               | 
               | > Parallel construction is a law enforcement process of
               | building a parallel, or separate, evidentiary basis for a
               | criminal investigation in order to conceal how an
               | investigation actually began.[1]
               | 
               | > In the US, a particular form is evidence laundering,
               | where one police officer obtains evidence via means that
               | are in violation of the Fourth Amendment's protection
               | against unreasonable searches and seizures, and then
               | passes it on to another officer, who builds on it and
               | gets it accepted by the court under the good-faith
               | exception as applied to the second officer.[2] This
               | practice gained support after the Supreme Court's 2009
               | Herring v. United States decision.
        
               | neodymiumphish wrote:
               | While I'm sure it happens, I don't think that "evidence
               | laundering" is particularly common, especially at the
               | federal level. Cases I ran required an "initial
               | notification" that succinctly described how our agents
               | were notified of the potential criminal activity. The
               | fear of having a case thrown out, or being turned down
               | months into a high-level investigation because an
               | attorney is uncomfortable with the likely outcome, is
               | huge in ensuring a valid investigation is run.
               | 
               | Now, that's not to say that cops wouldn't do this in
               | order to finally get a case around a particular subject
               | who was able to sidestep previous investigations or
               | something. I just doubt that it happens often enough to
               | be worthwhile.
        
               | [deleted]
        
               | [deleted]
        
           | [deleted]
        
           | malka wrote:
           | Good. They will then collect useless data that a lawyer will
           | destroy in court.
        
         | foxylad wrote:
         | Add one more: Anyone publicly attacking Signal's privacy in the
         | future is painting a _very_ large target on their forehead.
        
           | neodymiumphish wrote:
           | There's a difference between attacking their privacy (which
           | is fair and should be done regularly if users' privacy is at
           | stake) and claiming access to secure data that is wholly
           | untrue.
        
         | crb002 wrote:
         | It was brazen enough to pop an iTunes GUI a few years back.
        
         | microtherion wrote:
         | IANAL, and I don't speak for Apple, but as far as I can tell,
         | the part about Apple is nonsense.
         | 
         | CoreFoundation is open source: https://github.com/opensource-
         | apple/CF
         | 
         | libdispatch is open source: https://apple.github.io/swift-
         | corelibs-libdispatch/post/libd...
         | 
         | ASL is open source:
         | https://opensource.apple.com/source/syslog/syslog-349.1.1/li...
         | 
         | The objective C runtime is open source:
         | https://github.com/opensource-apple/objc4/blob/master/APPLE_...
         | 
         | icu, pthread, zlib, and libxml did not even originate at Apple.
        
           | j16sdiz wrote:
           | Yes, but the copy shipped is signed by Apple. i.e. they did
           | not compile their own copy.
        
             | atat7024 wrote:
             | > signed by Apple
             | 
             | Signed by Apple's key!
        
           | valleyer wrote:
           | MobileDevice.framework isn't open source.
        
         | op00to wrote:
         | > It attacks Cellebrite's ability to operate by casting doubt
         | on the reports generated by the product that their customers
         | may wish to use in court.
         | 
         | Fortunately, parallel construction means you never really have
         | to throw out bad evidence as long as you can find some good
         | evidence too!
        
           | maccam912 wrote:
           | Knowing that at least one row of data in a database might
           | have been modified randomly means you can't fully trust any
           | one line in the database completely.
           | 
           | It reminds me of the story of
           | https://en.wikipedia.org/wiki/Annie_Dookhan
        
             | neodymiumphish wrote:
             | Sure, but the data on the phone will lead you to evidence
             | in the real world, which will be meaningful proof that can
             | be used in court.
        
               | lostcolony wrote:
               | You either will have to come up with a plausible
               | (literally, 'warranted') way to have gotten that data in
               | the real world without relying on the data on the phone
               | as the reason you went looking, or it will likely be
               | thrown out due to it being "Fruit of the poisonous tree".
        
               | neodymiumphish wrote:
               | False data isn't FOTPT.
               | 
               | If I search a phone with a tainted UFED and get a
               | conversation between Bob (my subject) and Carl (his
               | friend) about the drugs they're selling, that
               | conversation either exists or doesn't exist. Now, let's
               | assume that the court won't accept this evidence, based
               | on a defense argument that it should be inadmissible
               | after seeing the vulnerabilities of UFED, as detailed by
               | Signal.
               | 
               | The next investigative step in to go interview and search
               | Carl, since there is probable cause to believe that a
               | conversation occurred about their drug dealing on his
               | phone. Unless I a) know my UFED is vulnerable and b) have
               | reason to believe the text conversation between Bob and
               | Carl is fake, my warrant for Carl's phone is valid. Now,
               | I search Carl's phone with the same UFED and find the
               | exact same conversation.
               | 
               | At this point, it's still possible for the UFED to have
               | made the conversation up on both sides and for both
               | extractions, and this would probably make the resulting
               | conversation (and potentially everything in the report)
               | inadmissible, but any admissions from Bob or Carl,
               | including based on questions asked about the conversation
               | itself, would still be admissible. I could show the
               | report to Bob and Carl as evidence against them and get a
               | confession, which would be admissible. Additionally, if
               | the court determines that the UFED report is inadmissible
               | based on the potentially for it to be forensically
               | unsound, I would still have the phones themselves. UFED
               | (except in rare circumstances) requires the phone to be
               | unlocked before it can make its extraction. As such, I
               | could manually browse the phone to the conversation in
               | question and take photos of the phone with the real
               | conversations between Bob and Carl. I could also verify
               | through an ISP/messenger app that evidence of those
               | conversations occurred (for example, metadata
               | demonstrating matching times and message sizes that align
               | with the potentially-fabricated message).
               | 
               | The FOTPT defense only applies to illegally obtained
               | evidence. Assuming you obtained a valid warrant or
               | consent to conduct the search, there was nothing illegal
               | about the UFED extraction that would make the FOTPT
               | defense applicable.
        
               | voiper1 wrote:
               | In your example, it's true that you could question Carl,
               | but the a warrant to search Carl based on the false data
               | should be overturned later.
        
               | neodymiumphish wrote:
               | It's not knowingly false, so the warrant would remain
               | valid.
        
               | op00to wrote:
               | https://www.reuters.com/article/us-dea-sod/exclusive-u-s-
               | dir...
               | 
               | ~~~ The undated documents show that federal agents are
               | trained to "recreate" the investigative trail to
               | effectively cover up where the information originated, a
               | practice that some experts say violates a defendant's
               | Constitutional right to a fair trial. If defendants don't
               | know how an investigation began, they cannot know to ask
               | to review potential sources of exculpatory evidence -
               | information that could reveal entrapment, mistakes or
               | biased witnesses. ~~~
               | 
               | If you believe any of "fruit of the poisonous tree" stuff
               | makes any difference, I've got a bridge to sell you.
               | There is clear evidence that DEA agents are trained to
               | create a "clean" story of evidence around the illicit
               | information they get.
        
               | neodymiumphish wrote:
               | It doesn't matter. This story/example from Signal has
               | nothing to do with FOTPT.
        
               | tuwtuwtuwtuw wrote:
               | Sounds like a US/UK-centric view of things. There's many
               | countries where evidence can be used in court regardless
               | of how it was obtained, Swedish and Germany to name two.
        
               | lostcolony wrote:
               | Fair point.
        
               | sneak wrote:
               | That's precisely what parallel construction is: a lie
               | told by investigators to the court to sidestep the poison
               | tree, bolstered by real evidence specifically gathered to
               | lie outside of the branches of same.
               | 
               | It's a method that crooked law enforcement uses to
               | deceive courts. It's so common as to have its own name
               | now.
        
               | lostcolony wrote:
               | Right, but that implies you can construct an entire chain
               | that doesn't include checking their phone. Just pointing
               | out, per the post i was replying to, it's not simply use
               | the phone, get other evidence, don't worry about the
               | phone's evidence being thrown out.
        
               | op00to wrote:
               | That's literally what it is, except "get other evidence"
               | means "construct a plausible story that gets you to the
               | same point".
        
               | neodymiumphish wrote:
               | No, that's not the case here. You don't need a parallel
               | construction in this example, because the UFED extraction
               | (even if tainted by a similar exploit) wasn't illegally
               | obtained.
        
               | op00to wrote:
               | Didn't know that, thank you!
        
         | rodgerd wrote:
         | > It makes a thinly-veiled threat that any random Signal user's
         | data may actively attempt to exploit their software in the
         | future and demonstrates that it's trivial to do so.
         | 
         | That does not make me feel good about Signal.
        
           | rpdillon wrote:
           | I've seen this reaction a few times. Can you say more?
           | Presumably Signal users value privacy, and the implication is
           | that when hacking tools used to violate that privacy are
           | applied to a device running Signal, it may try to interfere
           | and prevent the extraction to some degree. This seems like an
           | ideal feature for a private messenger.
           | 
           | In contrast, it would strike me as strange if a Signal user
           | switched to another messenger that allowed the data
           | extraction because they were uncomfortable with Signal
           | blocking it.
        
             | Utanith wrote:
             | It's kind've hard to argue about having random unknown data
             | laying around, but...
             | 
             | The insinuation that my device may be host to something
             | potentially malicious is concerning. It gets a little worse
             | that it can change, without notice. I'd tend to trust
             | Signal and their security, but the potential for that
             | mechanism to be hijacked is always present. They've
             | certainly made it hard, though, and I think the folks at
             | Signal are probably clever enough that my anemic
             | observations don't tell the whole story.
        
               | atat7024 wrote:
               | > The insinuation that my device may be host to something
               | potentially malicious is concerning. It gets a little
               | worse that it can change, without notice.
               | 
               | Do you use an iPhone or a phone with Google Play Services
               | on it?
               | 
               | Those both have the technical capability of receiving
               | targeted updates.
        
               | codethief wrote:
               | Not just that. In the case of Google Play Services,
               | SafetyNet also downloads random binary blobs from Google
               | and executes them as root. Makes me feel a lot... _safer_
               | about my phone.
        
               | codethief wrote:
               | Everyone can inspect the Signal app's source code,
               | though, and make sure that nothing funny is happening
               | with the "aesthetically pleasing" files it downloads.
        
       | hellothestateis wrote:
       | kmk
        
       | not1ofU wrote:
       | How do Cellebrite maintain "Chain of custody"? If they need to
       | modify (hack) the device to get access. I was of the
       | understanding, that if any file is modified then "chain of
       | custody" is no longer in good standing, and therefore cannot be
       | used as evidence.
        
       | akerro wrote:
       | This isn't the first time moxie0 found something important on a
       | street, is it?
        
       | maybelsyrup wrote:
       | This rocks so hard. Also the Prodigy soundtrack! Takes me back.
        
         | alfiedotwtf wrote:
         | Hack the Planet o/
        
       | WrtCdEvrydy wrote:
       | This is something I have personally looked at as an owner of a
       | UFED touch device (1st gen). By default your software runs in a
       | non-priviledged account but who's to say one of files isn't just
       | straight up being read by FFMPEG and adding or removing evidence
       | from the final report.
       | 
       | The official Cellebrite policy has always been "don't worry, if
       | you get stuck, we can send you an expert to testify to the
       | reliability of the scientific evidence due to previous cases" but
       | what happens when the pyramid of previous cases fall apart? Do
       | you suddenly own a paperweight?
       | 
       | I've also published papers (with NIST's help) on using consumer
       | grade hardware for forensics and why testing your tools across a
       | wide variety of scenarios is critical.
        
         | tediousdemise wrote:
         | > _As just one example (unrelated to what follows),_ their
         | software bundles FFmpeg DLLs that were built in 2012 and have
         | not been updated since then.
         | 
         | This purported vulnerability does not rely on FFmpeg, hence the
         | disclaimer.
        
       | waltwalther wrote:
       | This is a really great piece. I have two observations.
       | 
       | 1) "..saw a small package fall off a truck ahead of me..."
       | 
       | 2) The very last paragraph is just great!
        
       | hnrodey wrote:
       | I have a new found perspective for the malware/spyware industry
       | after watching The Dissident.
       | 
       | I am SO IMPRESSED with this middle finger from the Signal team.
       | 
       | https://www.imdb.com/title/tt11382384/
        
       | joshgoldman wrote:
       | I like how the CEO bashes other countries and deliberately
       | doesn't mention USA as a customer of Cellebrite
        
       | tGr5lGf7 wrote:
       | Cellebrite doesn't even have a bug bounty programme or contact to
       | report their bugs.
       | 
       | Last year I've managed to gain partial access to one of their
       | systems and it took me weeks emailing their internal email
       | addresses to finally fix the bug. They were total ass about it.
       | 
       | Now I've got complete access to their entire database and I don't
       | know what do. Can HN advise?
        
         | [deleted]
        
         | kjjjjjjjjjjjjjj wrote:
         | You should not treat an unethical company ethically.
        
         | thricegr8 wrote:
         | Post is here and let folks take a look.
        
           | exikyut wrote:
           | Really _REALLY_ bad idea - this is one of law enforcement 's
           | larger pet gadgets and companies, so the GP would not only
           | have a particularly enthusiastic mob coming after them, said
           | mob's pitchforks would have automatic cannon launchers and
           | EMPs and push-button-activated nunchucks and all kinds of
           | other crazy things that aren't legal for standard-issue
           | pitchforks.
           | 
           | So if the database is fingerprintable to the GP specifically
           | in any way, they're very very dead. And the random username
           | doesn't even count here; they probably didn't post from Tor,
           | so their real IP is connected to this post.
        
             | Y_Y wrote:
             | I think it's a fair guess that a security researcher like
             | that knows how to post on hn without leaving their home
             | address. It's not particularly difficult.
        
         | vorpalhex wrote:
         | Well definitely don't share it with DDOS secrets, news outlets
         | or any other major company that would potentially report on it.
         | That would be very bad press for Cellebrite, and if they
         | connected it to you they could be very annoying - though again,
         | they would need pretty good evidence connecting it to you and
         | things like TOR and proper privacy practices would make that
         | very difficult. So definitely don't do that, or use something
         | like tails to post it to multiple SecureDrop outlets.
        
         | sneak wrote:
         | This definitely isn't a trap.
        
       | p4bl0 wrote:
       | I hope Cellbrite users like the rhythm and lyrics of _Never gonna
       | give you up_.
        
       | tazeg95 wrote:
       | "I was recently out for a walk when I saw a small package fall
       | off a truck ahead of me."... I I laughed :)))
        
       | temptemptemp111 wrote:
       | Amazing that no security minded people even consider Moxie &
       | Cellebrite being in cahoots. "But that's anti-semitic!" Take your
       | head out of the sand and realize that this doesn't apply to 98+%
       | of "semitic" people, by definition.
        
       | qyi wrote:
       | >Since almost all of Cellebrite's code exists to parse untrusted
       | input that could be formatted in an unexpected way to exploit
       | memory corruption or other vulnerabilities in the parsing
       | software, one might expect Cellebrite to have been extremely
       | cautious.
       | 
       | >Looking at both UFED and Physical Analyzer, though, we were
       | surprised to find that very little care seems to have been given
       | to Cellebrite's own software security.
       | 
       | People keep saying this. It has never changed since the 90s.
       | There is no bar to become a "software engineer".
        
       | caeril wrote:
       | Something about this smells a little off.
       | 
       | If Moxie can get his hands on these devices and hack them, why
       | can't Apple or Google, with all their resources, seem to be
       | capable of REing them to fix the mobile device bugs they
       | currently exploit?
       | 
       | Tinfoil hat perspective suggests they don't want to.
        
       | swyx wrote:
       | my TL;DR (but its a damn good read and funny too)
       | 
       | - Cellebrite helps oppressive regimes read your messages
       | 
       | - Signal keeps your messages private
       | 
       | - Cellebrite announces "Signal support"
       | 
       | - Signal finds 9 years of vulnerabilities in Cellebrite
       | 
       | - Signal permanently pwns Cellebrite
       | 
       | You come at the king, you'd best not miss.
        
       | alfiedotwtf wrote:
       | Damn. That video say it all.
        
       | cycomanic wrote:
       | >By a truly unbelievable coincidence, I was recently out for a
       | walk when I saw a small package fall off a truck ahead of me. As
       | I got closer, the dull enterprise typeface slowly came into
       | focus: Cellebrite.
       | 
       | That's just hilarious! Nice way of saying we got our hands onto
       | one of these boxes, but we don't want to reveal how. It fell of a
       | truck.
        
       | throwaway888abc wrote:
       | By a truly unbelievable coincidence, I was recently out for a
       | walk when I saw a small package fall off a truck ahead of me.
       | 
       | Nailed it!
        
       | tony101 wrote:
       | A reminder that you can pair lock your iPhone to prevent analysis
       | by Cellebrite or similar tools:
       | https://arkadiyt.com/2019/10/07/pair-locking-your-iphone-wit...
        
         | moduspol wrote:
         | All of these are based on the assumption that the attacker has
         | physical access to the _unlocked_ phone, right?
         | 
         | I'm trying to understand the risk profile here.
         | 
         | I guess I see the value for, e.g., a border crossing, where
         | they can inconvenience you and ask you to unlock your phone,
         | but instead of flicking through your messages briefly, they
         | authorize a pairing and quickly backup your entire disk
         | content. You expected a quick perusal by a human, but
         | unknowingly gave them a lot more. If you've blocked pairing,
         | they can't get nearly as much data as quickly.
         | 
         | But if you're being investigated for committing a crime,
         | everything we think we know about device unlocking is still
         | true, right? They'd need me to unlock it before it'd trust a
         | new device to pair to, and they'd need a court order to get me
         | to unlock it for them. Five quick taps of the power button and
         | biometric unlocks are off--now they need my passcode.
         | 
         | Perhaps there's still value, even in that case, in that if I
         | were compelled via court order to give my passcode, they still
         | can't quickly / easily dump the disk contents from a device
         | pairing. Although I imagine if you have the passcode there's
         | probably many other ways of accomplishing the same result.
        
           | d110af5ccf wrote:
           | > if I were compelled via court order to give my passcode
           | 
           | In the US that won't work if unlocking the device requires a
           | password or pin. In practice, you can't be compelled to
           | provide that unless you openly admit that you know it. (Even
           | then, the 5th amendment might afford you some protection.)
           | YMMV, IANAL, etc.
        
             | moduspol wrote:
             | IANAL but AFAIK you can be held in contempt of court if you
             | don't provide it when asked if they're already convinced
             | it's yours and has incriminating evidence on it. Article
             | below, although it looks like fairly recent (not super
             | established) jurisprudence.
             | 
             | [1] https://goldsteinmehta.com/blog/can-the-police-force-
             | you-to-...
        
               | d110af5ccf wrote:
               | At issue there is the "foregone conclusion" exception to
               | the 5th amendment. As far as I understand things you've
               | lost the case by that point anyway.
               | 
               | Even then, I believe there would still be the additional
               | issue of demonstrating that the defendant actually knows
               | the password. Which is why I previously mentioned that if
               | you openly admit to knowing the password then you likely
               | have a problem. (This came up in a case where the
               | defendant admitted to the FBI that he was capable of
               | decrypting an external hard drive but refused to do so
               | because "we both know what's on there".)
        
               | moduspol wrote:
               | > At issue there is the "foregone conclusion" exception
               | to the 5th amendment.
               | 
               | The unclear part seems to be how strong the evidence
               | needs to be that the device is yours and that the
               | evidence is on there. In this case, his sister testified
               | to both. But would it be strong enough with forensic
               | evidence alone? Unclear.
               | 
               | > As far as I understand things you've lost the case by
               | that point anyway.
               | 
               | Perhaps, but there may still be significance to what's on
               | that drive. There may be incriminating evidence there for
               | other crimes for which you're not yet being prosecuted.
               | 
               | > Even then, I believe there would still be the
               | additional issue of demonstrating that the defendant
               | actually knows the password.
               | 
               | They're saying the sister's testimony was sufficient to
               | prove that he knew the passwords previously.
               | 
               | Proving present-day capability to decrypt doesn't seem to
               | be necessary, at least in the article I linked.
               | 
               | > The federal court denied the Motion to Quash and
               | directed Doe to unlock the devices for the investigators.
               | Doe did not appeal, but he refused to unlock some of the
               | devices, claiming that he had forgotten the passwords. He
               | was eventually held in contempt by the District Court,
               | and the Court ordered that he remain in federal custody
               | until he was willing to unlock the devices.
               | 
               | The accused claimed he could not decrypt the hard drive
               | because he had forgotten the passwords, but he was still
               | being held in contempt.
        
               | dodobirdlord wrote:
               | > The unclear part seems to be how strong the evidence
               | needs to be that the device is yours and that the
               | evidence is on there.
               | 
               | The 5th amendment protects you from having to testify
               | against yourself, but it doesn't protect you from having
               | to turn over incriminating evidence against yourself. The
               | 4th amendment protects your stuff, but only up to the
               | point of requiring probable cause for a warrant.
               | 
               | At issue in these sorts of encrypted storage scenarios is
               | whether you would be incriminating yourself _by
               | demonstrating that you know the password_. Knowing the
               | password for an encrypted device basically proves that it
               | 's your device, so forcing you to decrypt a device would
               | amount to forcing you to testify against yourself in the
               | event that there is doubt about whether the device is
               | yours.
               | 
               | So to force you to decrypt a device there needs to be a
               | warrant for the contents, and it needs to be no doubt
               | about the fact that it is indeed your device. So it needs
               | to be a foregone conclusion that the device is yours, but
               | only requires probable cause to believe that something
               | specific and illegal is stored on the device.
        
               | moduspol wrote:
               | Thanks. That helps a lot to clarify.
        
           | carstenhag wrote:
           | > unlocked phone
           | 
           | Well, mostly yes, that's considering Cellebrite doesn't have
           | 0-days or other exploits which can send a SMS to the device
           | or similar things. Using Cellebrite's software you can also
           | send silent SMS, so it's not far off either.
           | 
           | A german Cellebrite ambassador showed me and colleagues the
           | mentioned tools of the blog post and told us he participates
           | at Law Enforcement raids. At 6 in the morning they raid the
           | houses of the suspects, detain them and immediately ask for
           | PINs and passwords. He said that surprisingly often it works
           | and no further decryption tries have to be performed.
        
         | matheusmoreira wrote:
         | Are there similar features for Android devices? A database of
         | Cellebrite-resistant phones, perhaps?
        
         | Anechoic wrote:
         | Do we (reasonably) know if this still works?
        
           | atVelocet wrote:
           | This still works as written. Just test it yourself with a Mac
           | and Apple Configurator.
        
             | Gaelan wrote:
             | I mean, "the iPhone prevents well-behaved software from
             | accessing data without a password" and "software, known to
             | exploit vulnerabilities to get around security features,
             | currently doesn't have any such exploits" are very
             | different.
        
               | ASalazarMX wrote:
               | Every stone we can put in the way of surveillance helps.
        
             | Anechoic wrote:
             | My question was ambiguous, what I meant was whether or not
             | there were any known exploits to work around pair locking
             | (all of my iOS devices are pair-locked). I didn't know
             | about the exploit that lights0123 linked to, but it appears
             | that has been fixed.
        
           | lights0123 wrote:
           | There was a vulnerability in this technique that was fixed in
           | iOS 11: https://labs.f-secure.com/advisories/apple-ios-host-
           | pairing-.... If someone found another vulnerability and
           | shared it with Cellebrite, then it doesn't work. If they
           | haven't, then it still does.
        
       | upofadown wrote:
       | They literally said the unit fell off a truck. Funny...
       | 
       | Correctly me if I am wrong, but did they really say they were
       | going to be doing active attacks against Cellebrite units? Also
       | funny... but they probably are not actually going to be doing
       | that.
        
         | kbenson wrote:
         | They didn't actually say anything of the sort. They may have
         | implied some stuff. Anything they did imply wouldn't be an
         | active attack though, it would be a passive one, triggered only
         | if Cellebrite tried to gather data from the Signal app on
         | phones. Not gathering info from a phone, or not gathering
         | Signal data from a phone, would both be ways Cellebrite could
         | avoid this potential passive attack.
        
           | ev1 wrote:
           | I read nothing about an attack of any method or type at all.
           | 
           | If Cellebrite decides to punch a spiky rock they could have
           | just not done that in the first place.
        
           | ASalazarMX wrote:
           | The digital equivalent of "stop hitting yourself".
           | Notwithstanding their crypto issue, this gives me renewed
           | confidence in Signal's team.
        
             | pavon wrote:
             | To me it seems more like the equivalent of leaving booby
             | trapped packages to be found by porch pirates. Or putting
             | laxatives (or worse) in your sandwich to get back at the
             | unknown coworker stealing your lunch. Both of which are
             | considered illegal in the US.
             | 
             | Assuming these files actually contain exploits. Maybe they
             | do maybe they don't. You feeling lucky Cellebrite?
        
               | phyzome wrote:
               | The question of whether damaging reports would be illegal
               | is separate from whether booby traps are illegal. And
               | they're not, in the broad case: Booby trapped packages
               | are only illegal if they cause bodily harm or damage or
               | are negligent along those lines.
        
               | pavon wrote:
               | The actual crime would be different; the former would be
               | assault, while the latter would be unauthorized access
               | under the CFAA, but I think the principle applies to
               | both. In both cases the intent to cause harm exists, and
               | doesn't become irrelevant just because the victim had to
               | put themselves in a situation to trigger that harm. If
               | anything I think there is a _stronger_ case against
               | leaving exploits around where software might scan them,
               | because while stealing is illegal, scanning files
               | typically is not (if you have legal rights to access the
               | device, via ownership or warrant).
        
       | crb002 wrote:
       | https://www.iowajustice.com/ is _amazing_ at UFED defense.
        
       | Klonoar wrote:
       | If it's true that you can grab a Cellebrite hardware piece
       | without too much difficulty (Ebay, etc - and note I'm not
       | speaking from expertise so someone please fact check me), I'd
       | find it hard to believe Apple wouldn't have done this kind of
       | inspection themselves and/or noticed those DLLs being shipped.
       | 
       | Curious if there'll be a response of sorts.
        
         | polar wrote:
         | I am reasonably confident that Apple is a Cellebrite customer.
         | Their security team certainly has access to forensic tools from
         | other vendors. That team also spawned BlackBag Technologies,
         | which is now part of Cellebrite.
        
           | saagarjha wrote:
           | Apple uses Cellebrite devices in their stores to transfer
           | data from devices, I believe.
        
       | joeblau wrote:
       | Signal is almost like anti-virus software against Cellebrite.
        
       | tediousdemise wrote:
       | To be fair, this vulnerability disclosure is worthless, because
       | it wasn't actually disclosed--the true vulnerability is purported
       | to be in the file that Signal uses to execute arbitrary code, of
       | which the details are not shared. We are relying on pure trust
       | that the video demonstration of the purported vulnerability is
       | not a forgery.
       | 
       | Additionally, I see from the video that the purported
       | vulnerability is present in UFED version 7.40.0.229. There is
       | nothing stopping Cellebrite from patching this purported
       | vulnerability, and shipping trustworthy versions of UFED going
       | forward.
       | 
       | If there is a concern that the purported vulnerability still
       | exists, the burden of proof will be with the person claiming the
       | vulnerability exists, _for each new version of UFED_. Cellebrite
       | doesn't even need to implement actual code, but merely increment
       | the UFED version number. It will be an endless cat and mouse game
       | driven by baseless claims from both sides.
       | 
       | Since this vulnerability has not been reproduced by third
       | parties, it could be equally likely that Signal is using a psyop
       | rather than exploiting a genuine vulnerability. In either
       | scenario, it casts doubt on Cellebrite; the damage is done by
       | convincing you, the reader.
        
         | amscanne wrote:
         | The post seems to provide a straight-forward map to at least
         | one vulnerability. If they have FFMPEG DDLs that have not been
         | updated since 2012 and they are used on files found on the file
         | system, you just need to find a relevant vulnerability and
         | craft an appropriate media file. These vulnerabilities are
         | well-known and well-documented. It just doesn't point to the
         | specific DLL & CVE, but otherwise seems like it would be
         | relatively easy to figure out.
        
         | sneak wrote:
         | Many vulnerabilities are disclosed without simultaneous
         | disclosure of the PoC. That doesn't make it worthless.
         | 
         | Also, not disclosing specifics is reasonable here, given that
         | the vendor is themselves known for using, hoarding, and selling
         | access to 0days.
         | 
         | There is no obligation for a researcher to share their research
         | with such a corrupt vendor.
        
           | tediousdemise wrote:
           | I agree that the vendor is detestable, but we must decouple
           | that sentiment from the idea that this blog post compromises
           | Cellebrite's product or credibility in any way.
           | 
           | As it stands, the vulnerability is not reproducible by anyone
           | other than Signal. Reproducibility is key in the scientific
           | method and in the court of law.
        
       | rubatuga wrote:
       | Truly a jaw dropping blog post, as the top comment currently
       | states, Apple may be legally required to at the very least,
       | comment on this situation.
        
         | DaiPlusPlus wrote:
         | > Apple may be legally required to at the very least, comment
         | on this situation.
         | 
         | "Required" to comment? By whom and for what reason?
        
           | mhuffman wrote:
           | >"Required" to comment? By whom and for what reason?
           | 
           | By stockowners who might not like their valuable IP used in
           | this way or by this company without permission?
        
           | oh_sigh wrote:
           | Sending a cease and desist to Cellebrite for shipping their
           | DLLs in their product I imagine.
           | 
           | Obviously there may be some backchannel, but that is probably
           | how it would go if you assume Apple and Cellebrite have no
           | relationship.
        
             | grumple wrote:
             | Would they have a relationship? Cellebrite is an ant to
             | Apple. Why would Apple risk credibility and security by
             | helping them?
        
               | coldcode wrote:
               | Because Apple cares a lot about their security, and the
               | perception of security, and they have a lot of lawyers
               | with nasty teeth. Using stolen unlicensed Apple
               | technology to hack people's iOS devices is like eating a
               | bear cub in front of mama bear.
        
             | mintplant wrote:
             | They _could_ send such a C &D, and they may be inclined to
             | for the sake of public perception, but what would "legally
             | require" them to do so?
        
               | chordalkeyboard wrote:
               | If they ignore cellebrite using their stuff they may have
               | waived their right to be upset about someone else doing
               | the same thing.
        
               | DaiPlusPlus wrote:
               | Copyright law isn't the same thing as Trademark law.
               | Copyrights don't expire because the rightsholder failed
               | to enforce their rights, only trademarks do.
        
               | Y_Y wrote:
               | Vigilantibus non dormientibus aequitas subvenit.
               | 
               | The principles of laches may still apply and provide a
               | defence for Cellebrite if Apple makes an "unreasonable
               | delay".
        
         | sneak wrote:
         | Don't confuse the thing where a company has to defend its
         | trademarks to keep them with copyrights (which do not require
         | active defense to maintain).
         | 
         | This, if Apple does pursue it, is a copyright matter, not
         | trademark.
        
       | idlewords wrote:
       | This is pretty irksome. I get how satisfying it must feel, but
       | the one thing I want as a Signal proponent is for the app to be
       | _boring_ and reliable. That means make it easy to use enough to
       | be mainstream, squash bugs, and do all the lovely security work
       | you do.
       | 
       | That does not mean adding stuff like untraceable cryptocurrency
       | payments or very publicly tweaking the noses of law enforcement,
       | and bragging about how you're putting exploits in your app to
       | hack them.
       | 
       | This isn't 1993 and the last thing we need is more pretexts to
       | ban E2E encrypted apps in the countries where they're needed the
       | most. I think this trades a moment's satisfaction for a very bad
       | long-term outcome.
        
         | g_sch wrote:
         | The problem with being boring while attacking powerful
         | institutions (like LEOs or nation states) is that it only works
         | as long as you're small enough to stay below their radar. After
         | a certain point, the material reality will sink in that you're
         | a threat, and they're going to take action against you
         | regardless of how you carry yourself. It's totally possible,
         | given that we're starting to hear more and more accounts of
         | powerful people using Signal, that we're approaching that
         | tipping point, and a more gloves-off approach might be
         | necessary.
         | 
         | That being said, I agree with you 100% on the cryptocurrency
         | payments issue and think that was a misstep on their part.
        
         | jjoonathan wrote:
         | Signal isn't going to actually do it, they know how that would
         | end, they're just playing the FUD game in the other direction.
         | Which I am 100% on board with.
        
           | zie wrote:
           | The client code is open source, so it should be pretty easy
           | to tell if they actually do it.
        
             | mannerheim wrote:
             | I would assume their aesthetically pleasing files would not
             | be part of their client code since the clients are fetching
             | these files from Signal.
             | 
             | So whether they're fetching aesthetically pleasing files
             | would be easy to tell, but trickier to tell if those files
             | actually have payload.
        
               | PeterisP wrote:
               | Automatically open the files with Cellebrite software
               | tools in a sandbox environment?
        
               | mannerheim wrote:
               | Wouldn't necessarily work:
               | 
               | > Files will only be returned for accounts that have been
               | active installs for some time already, and only
               | probabilistically in low percentages based on phone
               | number sharding.
               | 
               | You would have to have an already existing Signal account
               | that's been around for some time and hope you get sent
               | one of these files.
        
           | idlewords wrote:
           | Maybe the one thing worse than boasting that you're putting
           | malware in your product is boasting about it and not doing
           | it.
        
             | rOOb85 wrote:
             | They are not putting malware into their app. They are
             | adding athletically pleasing files to their app. Is it
             | Signals fault if someone else's software doesn't work
             | properly with them? How can Signal test every piece of
             | software to make sure it's compatible with their own
             | software? Especially when the other software is using
             | Signal in a unintended way.
             | 
             | It's not signals job to secure 3rd party software, that's
             | entirely on the 3rd party.
        
               | PeterisP wrote:
               | Intent matters, come on, your arguments are ridiculuous.
               | If one of the aesthetically pleasing files turns out to
               | contain an exploit targeted at Cellebrite software, then
               | it wouldn't be hard to convince a jury that this isn't a
               | coincidence but intentional malware, especially combined
               | with this wink-wink bragpost.
               | 
               | It's not Signal's job to secure third party software,
               | they can intentionally post incompatible data, but it
               | definitely is their job (just as everyone else's,
               | mandated by criminal law) to abstain from any activities
               | that would tamper with evidence. If that incompatible
               | data isn't limited to randomness or crashes but contains,
               | quoting the article "a file that executes arbitrary code
               | on the Cellebrite machine" or "undetectably alter
               | previous reports, compromise the integrity of future
               | reports (perhaps at random!), or exfiltrate data from the
               | Cellebrite machine" then it obviously was intentionally
               | made that way, which crosses the line and at that point
               | yes, it's definitely Signal's fault. If that gets
               | actually executed on a machine owned not by Signal but
               | e.g. some law enforcement agency, then Signal and any
               | involved developers personally may face criminal charges.
               | 
               | It does not even need to involve any computer specific
               | laws (though those are also likely to apply) - if there's
               | an incident where evidence got disrupted, if there's
               | evidence that this incident was caused by "aesthetically
               | pleasing files" developed by Signal, and there's some
               | evidence (e.g. this blogpost) that they made these files
               | knowing that they might result in other evidence being
               | destroyed - that's completely enough, that's tampering
               | with evidence, a felony. Go directly to jail, do not
               | collect $200, don't expect sympathy from law enforcement
               | and the legal system.
               | 
               | In my personal opinion this is all FUD and
               | scaremongering, because actually doing so carries little
               | benefit and high risk for Signal. But, of course, no one
               | can be sure.
        
               | Dylan16807 wrote:
               | You're allowed to host malware if you want. If you _tell
               | people not to run it_ then how can it be your fault? That
               | 's not tampering with evidence.
        
               | rimliu wrote:
               | Because Celebrite's software is shown to be exploitable,
               | how do you know it was Signal's files and not someones
               | else corrupting it?
        
             | mannerheim wrote:
             | Is it malware if users desire for their devices to be
             | resistant to surveillance tools?
        
               | spinny wrote:
               | goodware ??
        
               | PeterisP wrote:
               | Those are not related issues - it's malware or not
               | malware based on what it does or did (e.g. did it corrupt
               | data on someone else's computer system because it was
               | intended to do just that thing?) regardless of the reason
               | for placing it there.
               | 
               | If you can't figure out a way to satisfy your desire for
               | your devices to be resistant to surveillance tools with
               | legal means, well, then you can't satisfy that desire.
               | 
               | Furthermore, not only the ends don't justify the means,
               | the ends can be prohibited too - if you explicitly design
               | something to destroy your own data knowing that this data
               | would get used in a criminal investigation, that may be a
               | crime on its own (tampering with evidence/obstruction of
               | justice, location matters of course); you don't have to
               | testify against yourself, but destroying evidence is a
               | crime even if it's your property (e.g. throwing your gun
               | into a river after a shooting so it wouldn't be found)
               | and furthermore in that case the court may be allowed to
               | assume that the destroyed evidence was unfavorable to
               | you, that the data contained the damning things they
               | expected to find there - so if you want to protect your
               | devices from surveillance tools operated with a legal
               | warrant, you might want to consult a lawyer to find out
               | if that's a good idea in your jurisdiction, it may well
               | be worse for you than doing nothing.
        
               | tgragnato wrote:
               | > If you can't figure out a way to satisfy your desire
               | for your devices to be resistant to surveillance tools
               | with legal means, well, then you can't satisfy that
               | desire.
               | 
               | I fear this part of your argument is fallacious. A
               | peaceful and hilarious response to an abuse is not
               | illegal. An if it is, it should not be. This post just
               | highlights how petty the means and methods used by "some
               | companies" are. Moxie is rightfully mocking Cellebrite
               | and its customers, and it's fantastic.
               | 
               | About the obstruction of justice... If governments around
               | the world are having an appetite for abuses, we shall not
               | fall for it. There are other ways to get to criminals.
               | Tell state officers they can do their job without abusing
               | the private sphere of citizens.
               | 
               | It's Cellebrite devices that should be made illegal,
               | because "justice" should not depend on surveillance
               | tools. Just days ago the same US IC shared a memo/report
               | about the rise of authoritarianism and how western
               | democracies are threatened by it. Let's stop this double
               | standard.
        
               | mannerheim wrote:
               | It is software that many of us are perfectly content with
               | possessing on our devices. Cellebrite may not want it on
               | their devices, but it's not like we consent to Cellebrite
               | copying over our data. Holding us or Signal responsible
               | for this is akin to holding a dog or its owner
               | responsible for a burglar getting mauled - it would be
               | one matter if the dog mauled a guest, but you can hardly
               | blame either with unauthorised entry. In this case,
               | exploiting this can be considered a form of digital
               | rights management.
               | 
               | As for tampering with evidence, your claims are certainly
               | overbroad, otherwise one could consider Signal's
               | vanishing messages and deliberate lack of logging to be
               | tampering with evidence. In any case, an individual is
               | hardly responsible for those actions; they presumably did
               | not deliberately seek to destroy Cellebrite data since
               | Signal may choose to do this entirely at random.
        
             | matheusmoreira wrote:
             | Malware? Any countermeasure against state surveillance is a
             | good thing for us.
        
             | [deleted]
        
         | adiabat wrote:
         | I agree and find it more than irksome -- it really makes me
         | want to stop using Signal and stop recommending it to anyone;
         | moreso even than the recent scamcoin integration.
         | 
         | The reason I want e2e encryption is because I want control of
         | my devices, control of my information, control of what's going
         | on. It's not Moxie's phone to drop random files on to,
         | regardless of purpose. It's my phone, and I consider programs
         | that are doing things that I'm not aware of malware.
         | 
         | (Admittedly, Android is rife with stuff I don't want going on,
         | so it's not really my phone, it's Google's and Motorola's and a
         | bunch of other entities who have their tentacles in it, but
         | still...)
         | 
         | Maybe the last paragraph is a joke, and they have no intention
         | of randomly placing files on unwitting client machines. It's
         | open source, so I could compile the client myself and make sure
         | it's not doing anything funny. What a pain though. At that
         | point, so much trust is lost in the organization and codebase
         | that really I need to find some other messaging protocol / app
         | / network.
        
         | lvs wrote:
         | I think there's a chance the two topics you mention might be
         | connected. The loud backlash to the cryptocurrency scheme took
         | many by surprise and seeded doubt about Moxie's ideological
         | commitment. This post might be seen as an attempt to recover
         | some street cred.
        
         | spoonjim wrote:
         | Signal has a strong ideology. If you don't want to be a part of
         | that then don't use the app.
        
           | idlewords wrote:
           | Secure messaging apps aren't very thick on the ground. I
           | don't have to agree with Signal on every issue, I just want
           | them to ease off the 4-Loko.
        
       | amai wrote:
       | "These two MSI packages are digitally signed by Apple"
       | 
       | Couldn't Apple simply revoke the signature?
        
         | Strom wrote:
         | The digital signature is not needed to run the software.
        
           | NotEvil wrote:
           | The dll wil be flagged as malware in major av's if they
           | revoked it
        
       | philshem wrote:
       | I'd also like to get really excited about this. Can someone ELI5?
        
       | colmmacc wrote:
       | As a Signal user and moxie fan I love that post, but I worry that
       | it places _Signal_ in legal peril from Apple.
       | 
       | My fear, and prediction, is that the authorities will frame this
       | as an even more egregious attack on law enforcement and that
       | interfering with investigations is a crime (I'm not a lawyer, but
       | I play one in hacker news comments, and that sounds like a
       | crime). They'll lean on the app stores and the app stores will
       | lean on or remove Signal.
        
         | jjoonathan wrote:
         | 1. Any app could do it.
         | 
         | 2. Signal stirred FUD in a blog post. That's a _very different
         | thing_ from actually doing it.
        
           | jaywalk wrote:
           | Well, if you read the whole blog post, it certainly _seems_
           | like they 're actually doing it.
        
             | jjoonathan wrote:
             | Nah. The cost/benefit of saber rattling makes tons of sense
             | while the cost/benefit of actually doing it makes much less
             | sense. Probably.
             | 
             | No amount of certainty about Marlinspike's actions should
             | comfort Cellebrite, though, because Moxie Marlinspike isn't
             | the only person allowed on the app store.
        
               | akerl_ wrote:
               | I'm not sure what you mean. The end of the post pretty
               | clearly describes the framework they're using to roll out
               | these exploits as latent files within the Signal app.
        
               | twright0 wrote:
               | The end of the post is extremely specifically and
               | carefully not describing a framework for rolling out
               | files to exploit these vulnerabilities; those files as
               | described do nothing, and serve only aesthetic purposes.
               | While it's easy to read that as a wink that they _are_
               | exploiting the vulnerabilities they found while
               | maintaining plausible deniability that they aren 't, it's
               | equally possible it's the other way around: they aren't
               | rolling out exploits but want people reading the blog
               | post to believe that they are. Or that they want to lay
               | out the framework so that others can do so, but aren't
               | actually going to follow through themselves. As written
               | it's essentially unverifiable, obviously on purpose.
        
               | phyzome wrote:
               | The optimal thing for them to do would be to build the
               | framework and ship partially corrupted JPEGs that don't
               | actually do anything nasty to Cellebrite. Cellebrite can
               | verify that the machinery is there (not a totally idle
               | threat) but no one can prove that Signal has actually
               | done anything illegal. Cellebrite then wastes a bunch of
               | times gathering and analyzing the files without actually
               | learning anything from it. They also get more incentive
               | to start finding and fixing their software's
               | vulnerabilities, which throws off work schedules.
               | 
               | And Signal can develop a few land mines to deploy at any
               | time, and just... hold on to them for a rainy day.
        
               | [deleted]
        
               | jaywalk wrote:
               | Even if Signal put the files out there and explicitly
               | owned up to it, I struggle to see how it could be even
               | remotely illegal. It's not their fault some other
               | company's faulty product falls apart when it hits bad
               | data in _their_ app.
        
               | SirSourdough wrote:
               | Agreed. Obviously, I'm not a lawyer so who knows. But it
               | seems ridiculous that you could break into someone else's
               | device and run all of _their_ files and then come after
               | them legally because a file you effectively stole didn 't
               | run properly on your computer.
               | 
               | At some point if someone breaks through multiple levels
               | of advanced security to, say, steal your gun and then
               | shoot themselves in the face with it, whose fault is that
               | really...
        
       | qwertox wrote:
       | > Also of interest, the installer for Physical Analyzer contains
       | two bundled MSI installer packages named
       | AppleApplicationsSupport64.msi and
       | AppleMobileDeviceSupport6464.msi. These two MSI packages are
       | digitally signed by Apple and appear to have been extracted from
       | the Windows installer for iTunes version 12.9.0.167.
       | 
       | Couldn't Apple now sue Cellebrite?
        
         | the_lucifer wrote:
         | Yup, Signal just handed Apple's lawyers a loaded gun. Who knew
         | I'd be enjoying Signal and Apple tag-teaming Cellebrite.
        
           | qwertox wrote:
           | I wonder if they will. That would show it their "our
           | customers privacy is the most important thing for us"-stance
           | is something which they seriously mean.
        
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