[HN Gopher] Exploiting vulnerabilities in Cellebrite UFED and Ph...
       ___________________________________________________________________
        
       Exploiting vulnerabilities in Cellebrite UFED and Physical Analyzer
        
       Author : derekerdmann
       Score  : 696 points
       Date   : 2021-04-21 16:29 UTC (6 hours ago)
        
 (HTM) web link (signal.org)
 (TXT) w3m dump (signal.org)
        
       | [deleted]
        
       | 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
        
       | 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.
        
       | 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...
        
         | 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".
        
       | 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?"
        
       | 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.
        
           | 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!
        
         | 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.
        
               | 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.
        
           | hprotagonist wrote:
           | or just flipping them off, which seems OK too.
        
           | 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
        
           | 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?
        
         | 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/
        
         | 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.
        
       | 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.
        
           | 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.
        
               | 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.
        
         | 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.
        
           | 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
        
       | 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.
        
             | 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.
        
               | 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.
        
         | 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.
        
           | 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.
        
           | 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.
        
               | 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.
        
           | 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.
        
           | 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...
        
         | crb002 wrote:
         | It was brazen enough to pop an iTunes GUI a few years back.
        
         | 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
        
         | 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.
        
         | 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.
        
       | 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.
        
       | 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
        
       | 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 :)))
        
       | 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.
        
           | 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.
        
           | 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?
        
       | 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.
        
       | 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.
        
       | 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.
        
           | 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.
        
             | mannerheim wrote:
             | Is it malware if users desire for their devices to be
             | resistant to surveillance tools?
        
               | spinny wrote:
               | goodware ??
        
             | matheusmoreira wrote:
             | Malware? Any countermeasure against state surveillance is a
             | good thing for us.
        
             | [deleted]
        
         | 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.
        
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