[HN Gopher] A phishing attack involving g.co, Google's URL short...
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       A phishing attack involving g.co, Google's URL shortener
        
       Author : zachlatta
       Score  : 164 points
       Date   : 2025-01-24 03:38 UTC (19 hours ago)
        
 (HTM) web link (gist.github.com)
 (TXT) w3m dump (gist.github.com)
        
       | aramsh wrote:
       | What's even more interesting is there is no DNS records for
       | important.g.co, which means they have found a way to create an
       | Google Workspace without verifying the domain but still able to
       | send emails like password resets.
       | 
       | It's definitely a glitch where you can send emails/transactional
       | emails from an unverified Google Workspace. My guess is that
       | their are protections for google.com and google domains but they
       | forgot to add the g.co domain, which allows unverified sending to
       | g.co and creation of workspaces.
        
       | gm678 wrote:
       | What I'm most curious about is how they were able to spoof the
       | email being sent from `workspace-noreply@google.com`. Given the
       | odd phrasing of 'password for important.g.co', perhaps this is
       | some strategy involving creating a 'parallel' account with the
       | same email and making use of it to send an official-looking email
       | as part of the scam?
        
         | zerocrates wrote:
         | Most likely they did something like sign up for
         | "important.g.co" in Workspace, then added the target as a user,
         | then reset that user's password, causing Google to send a real,
         | verified, from-Google message.
         | 
         | They can't control the contents of the message, but they used
         | the gmail "+" feature to cram the "case ID" onto the target
         | email they created the Workspace account for, making that seem
         | real.
        
           | markerz wrote:
           | But how did they MITM the verification code? Was the first
           | two presented to the attacker, and the rest was presented to
           | the email? Or were they able to MITM the whole email/code and
           | just shared the first two to gain trust?
        
             | Spoom wrote:
             | This sounds like they were using the "tap a button on your
             | device" 2FA method (see
             | https://support.google.com/accounts/answer/7026266). Not
             | sure of the details as to how they got to that page in the
             | first place, though the docs say that you can potentially
             | use it to recover your account.
             | 
             | Never trust an incoming call, especially if it's talking
             | about authentication problems you didn't know you had.
             | 
             | Googler, opinions my own (and I'm not an expert in this
             | particular space).
        
             | renewiltord wrote:
             | When you use a device to do 2FA, Google will display one
             | code on the logging in device screen and three on the 2FA
             | screen. This is so that the user doesn't just blindly hit
             | accept on the Gmail/YouTube app that hosts the 2FA prompt.
        
               | valleyer wrote:
               | A one in three risk of hitting the wrong button still
               | seems insanely high to me. Why is this 2FA method
               | deployed instead of things like "enter the code here"?
               | 
               | (I know it wouldn't necessarily have stopped this
               | phishing attempt.)
        
       | rekabis wrote:
       | > I asked if I could call back a phone number listed on
       | Google.com and she said sure - this number is listed on
       | google.com and you can call back with your case number, but there
       | may be a wait on hold and I might get a different agent. I
       | googled it and sure enough, it was listed on google.com pages. I
       | didn't call back though.
       | 
       | This is where a big mistake is. Always, _ALWAYS_ phone or contact
       | back using the company's official channels. Because if they have
       | sufficient info about you, scammers can make a call sound hella
       | legitimate, but one thing they still cannot do is pick up the
       | company's phone for them when you phone in. Especially if you
       | call from a hardline, which requires compromising the phone
       | company's switching equipment.
       | 
       | Even my father, nearly 86 with a 5th grade education and slowly
       | sliding into dementia, knows better than to uncritically accept
       | being directly contacted. He's already short-circuited several
       | scams (of various types) in the last few years by hanging up and
       | phoning back in himself.
        
         | jrochkind1 wrote:
         | > Especially if you call from a hardline,
         | 
         | I have no idea where I'd find one of those.
        
         | philipwhiuk wrote:
         | Yeah.
         | 
         | In reality the number your phone carrier provides is basically
         | a guess. It does in no way guarantee who is calling you.
        
         | pests wrote:
         | This used to not be safe though, in the age of landlines.
         | 
         | I forget the details, but most of the country was wired in a
         | manner that both parties of a call had to hang up to end the
         | connection.
         | 
         | You might hang up, go find the official phone number, but when
         | you pick the phone off the cradle you would still be in the
         | previous call. They could fake the dial tone and you would be
         | none the wiser.
         | 
         | I remember pranking friends with this back when I was young.
         | Harmless stuff.
        
           | quesera wrote:
           | I think this was in crossbar switches. The initiator of the
           | call had to hang up for something like 8 seconds.
           | 
           | This was useful if they called you and you answered in the
           | kitchen, but wanted to run to another room to talk. Not that
           | I think it was designed to be a feature! But I used it that
           | way.
           | 
           | If you didn't trust the caller, you could hang up, wait 10
           | seconds, then get a good clean real dial tone. Remember dial
           | tones?
           | 
           | Anyway none of this is relevant in modern switching systems,
           | much less cellular networks.
        
         | insane_dreamer wrote:
         | > This is where a big mistake is. Always, ALWAYS phone or
         | contact back using the company's official channels.
         | 
         | The problem, and the reason why that scam approach works half
         | the time, is that calling back is a huge PITA these days
         | between 1) endless routing menus or some "smart" AI bot that is
         | f*ing useless (seriously, I have never been helped to my
         | satisfaction by one of those), 2) long long long hold times to
         | get to a human, if you ever do, because every single company is
         | always "expecting greater than usual call volumes" -- wtf? call
         | volume distributions are Gaussian, ok? so adjust accordingly.
        
       | pavel_lishin wrote:
       | I know it's easy to second-guess someone after they've explained
       | that they're describing a scam, but:
       | 
       | > _The thing that 's crazy is that if I followed the 2 "best
       | practices" of verifying the phone number + getting them to send
       | an email to you from a legit domain, I would have been
       | compromised._
       | 
       | He _didn 't_ follow the first of those best practices. He just
       | looked up a phone number that the caller also read out to him,
       | _and didn 't call it_. And "Solomon" also explicitly told him he
       | _couldn 't_ call.
       | 
       | I honestly think that at this point, no incoming phone call can
       | ever be trusted.
        
         | ksala_ wrote:
         | I'd argue the second one was not followed either. Maybe I'm
         | misunderstanding the article, but I would not take a random
         | "your password has changed" as proof. I would need the caller
         | to send me an actual email from their personal work email
         | address (or ticket system?) with some actual, human
         | communications in it.
        
         | numbsafari wrote:
         | > no incoming phone call can ever be trusted.
         | 
         | They can't. And they haven't been for a while. Spoofing phone
         | calls is simply too easy, and nothing is being done to fix
         | that, despite the fact that it puts so many of us at risk. It's
         | not an insurmountable problem, technologically. It is literally
         | a lack of will and outcry from ordinary people, despite how
         | often this fact is used to abuse so many.
         | 
         | Credit Card companies have known this for a long time. My
         | credit card company will call and say "do not call back to this
         | number, call the number on the back of your card and use this
         | reference number".
         | 
         | That should absolutely be the norm at this point.
        
           | BobaFloutist wrote:
           | Telecoms know if a number is spoofed or not. All I want is
           | for them to wholesale steal the original Twitter "verified"
           | check, and use it to confirm that a call is not spoofed.
        
             | umanwizard wrote:
             | My iPhone (on Verizon) already does this.
        
             | HeatrayEnjoyer wrote:
             | The originating provider knows, but do providers downstream
             | know? If AT&T receives a call from $MadagascarPhoneCorp who
             | indicates the call is officially from $IndiaPhoneCorp, can
             | AT&T trust that?
        
         | lolinder wrote:
         | I don't even know where the idea that those are the best
         | practices came from.
         | 
         | The phone number best practice has always been constructed as
         | "call them back at a known good number, preferably one written
         | on paper or on your card". You certainly don't ask them to show
         | you where on the company website the phone number is listed.
         | 
         | And asking the person on the phone with you to send you an
         | email from a specific domain is likewise not something I've
         | ever seen recommended: that's one of several things you check
         | to see if an email is phishing (And only one of several! A good
         | domain isn't enough to clear an email!) But if you're already
         | on the phone with someone suspicious, the best practice has
         | always been to get off the phone with them immediately and call
         | a known number, not to ask the caller to prove themselves.
         | 
         | None of this is to blame OP for misunderstanding, it's just
         | very clear that we need to do better at communicating these
         | rules out to the world.
        
           | superq wrote:
           | But, if it _is_ listed on the company website, then..
           | 
           | But you're right: simply say "given that this is a sensitive
           | security matter, thank you for the heads up. Don't call me,
           | I'll call _you_ (click) "
        
             | bryanrasmussen wrote:
             | >But, if it is listed on the company website, then..
             | 
             | I'm sorry I'm going to have to call you, instead of you
             | calling me
             | 
             | Of course, the company phone number is right in the footer
             | of the website.
             | 
             | -- goes to open website from last email sent from company,
             | goes to colnbase.com.
        
       | blevinstein wrote:
       | Sounds really similar to my experience a few months ago. I
       | commented here about it.
       | 
       | https://www.reddit.com/r/googleworkspace/s/NtJpputXtg
       | 
       | There was something in Google workspace that allowed the scanners
       | to have an email sent to them, AND an additional and of their
       | choice. But when I asked about calling them back, I was told that
       | wasn't possible, which made me suspicious.
        
       | philfreo wrote:
       | Can someone explain point #9 in the gist? How'd they know part of
       | the two factor code?
        
         | jonas21 wrote:
         | The attacker was going through the sign in flow on their own
         | computer. In the MFA step, it shows you a number and asks to
         | you press the same number on your phone.
         | 
         | There's a screenshot of what this looks like here:
         | https://gist.github.com/zachlatta/f86317493654b550c689dc6509...
        
         | jsnell wrote:
         | It's not a two-factor code like you're thinking of. That code
         | is shown on the sign-in / account recovery page, to whoever
         | making that attempt. Then the same value has to be chosen on
         | the mobile device that's being used to authenticate that sign-
         | in.
         | 
         | The goal isn't to protect against phishing or social
         | engineering, but against people accidentally approving a sign-
         | in they didn't initiate.
        
           | joshuamorton wrote:
           | (specifically, there are "credential stuffing" style sign-in
           | attacks where an attacker logs in "suspiciously" at the same
           | time as a legit log in, possibly after forcing a log-out,
           | hoping you approve both your log in and theirs when you get
           | two, or ten pop-ups)
        
       | rvnx wrote:
       | It would be better if Google would react more strongly to such
       | attacks.
       | 
       | -> There is a sophisticated one where you can take over an
       | account via the Account Recovery flow, that is still actively
       | abused; tried to report, got "not a bug, triaging as abuse risk"
        
       | arccy wrote:
       | unless thinks they own important.g.co, they've just walked past
       | some glaring red flags, it doesn't even mention their domain in
       | the email.
        
       | do_not_redeem wrote:
       | As usual this started with an incoming phone call. If you ever
       | receive a phone call from a tech company, it's a scam. The caller
       | ID doesn't matter. The caller's accent (wtf) doesn't matter
       | either. It's a scam.
        
         | ripped_britches wrote:
         | Not if you're an app developer on their platform, they make
         | outbound calls to you. I'm sure there are other situations as
         | well.
        
           | do_not_redeem wrote:
           | If the consequences for letting that call go to voicemail are
           | any less severe than full account takeover by a script
           | kiddie, you're still better off never picking up.
           | 
           | Google in particular is famous for making it impossible to
           | contact a human. If Google calls you, before picking up,
           | consider whether you truly believe you're lucky enough to be
           | one of a handful of people in the world to ever get human
           | support from them.
        
           | lolinder wrote:
           | You still always assume an incoming call is a scam no matter
           | what. Hang up, look up, call back, in that order.
           | 
           | Very occasionally you might be making some poor customer
           | support person's job harder, but the vast majority of the
           | time you'll be hanging up on a scammer. You can be polite
           | about it, but firm and brief. "It's my policy to always call
           | back no matter what, nothing personal."
        
           | nodamage wrote:
           | For what purpose do they make these calls?
        
         | hbn wrote:
         | > The caller's accent (wtf)
         | 
         | You don't have to pretend to be confused.
         | 
         | The industry of Indian scam call centers is not a crazy
         | conspiracy invented by racists.
        
           | quesera wrote:
           | > _The industry of Indian scam call centers was not invented
           | by crazy racists._
           | 
           | Nor was the industry of Indian legitimate call centers.
           | 
           | You cannot glean any useful signal of legitimacy from the
           | caller's accent.
           | 
           | That's the WTF.
        
             | moi2388 wrote:
             | As if official Indian tech support is not a scam..
        
               | quesera wrote:
               | Support quality is a function of cost, which is a
               | function of customer value.
               | 
               | Low-margin businesses will hire low-cost support on
               | whatever continent it's available.
        
             | TheRealSteel wrote:
             | Almost all scam calls originate in India. It's absolutely
             | an indicator.
        
           | zb3 wrote:
           | However, now we have AI, so you shouldn't assume the call is
           | safe if the accent matches either...
        
       | nemothekid wrote:
       | I'm not sure if it's good thing or not but I've come to consider
       | that _any_ notification about a password being reset or a
       | fraudulent charge is phishing unless I initiate some action.
       | 
       | I always verify that I'm actually fucked and then take action.
       | This seems counter-intuitive but the deluge of phishing emails
       | makes me feel this is the safest option. I'd rather wait to
       | notice a fraudulent charge and dispute it, than leak info to a
       | random SMS number that claims (possibly truthfully) that someone
       | in Japan spent $9000 at the gucci store.
        
         | ronnier wrote:
         | Agreed. I do not follow any links, accept calls, etc. I go to
         | the site of origin and do what I need. Also be careful if you
         | search for the sites name on Google, still might click a fraud
         | site!
        
       | sethops1 wrote:
       | > Someone named "Chloe" called me from 650-203-0000
       | 
       | Nope. Rule #1 in today's environment is never pick up the phone.
       | If you're not expecting the call they can leave a message. And if
       | it's something you think is legitimate, get the authentic number
       | from a reputable source.
        
       | renewiltord wrote:
       | That's not verifying the phone number. I received a call from
       | Chase about a wire. I asked them for a code so I could continue
       | the conversation and then looked up the phone number on their
       | website and called that and talked through reps till I got to the
       | right department.
       | 
       | Caller ID being spoofed is the wrong way to think about this.
       | It's just that if someone walks up to you and says "Hey, I'm Jean
       | d'Eau and I'm President of the US" you don't think to yourself
       | "oh yeah he's definitely President and that's his name".
       | 
       | People can always tell you they're whoever they want to be. You
       | can either believe it or go find out if they are.
        
       | adrr wrote:
       | How did they send an email from google.com that passed DKIM and
       | SPF? Thats a huge concern.
        
         | jorams wrote:
         | It's specifically a password reset email. A Google Workspace
         | admin can send a password reset to any of their users, and it
         | will pass DKIM and SPF. The trick here is that apparently you
         | can sign up for Workspace with a g.co subdomain and, without
         | verifying the domain, can trigger a password reset to be sent.
        
           | layman51 wrote:
           | I'm still a bit confused around how they sent him the email.
           | Maybe they added him to the Google Workspace as a member?
        
             | jorams wrote:
             | Yeah they did. They added his email as a secondary email to
             | a Google Workspace user account, with the plus-address-
             | suffix including a "Case ID". Then they reset the password
             | of the user account, triggering this notification.
        
       | layman51 wrote:
       | This is the same type of phishing attack described here[1]. It's
       | still surprising to me how the SPF, DKIM, and DMARC all pass. If
       | I remember correctly, it's because they actually have a clever
       | way od getting Google to send an email to you by sharing a Google
       | Form with you or something like that.
       | 
       | [1]: https://news.ycombinator.com/item?id=42450221
        
         | 0xDEAFBEAD wrote:
         | Yep. Look at the screenshot. It seems they managed to trigger
         | one of Google's standard password reset emails.
        
         | ArkaneMoose wrote:
         | Based on the text at the bottom of the gist:
         | 
         | > Hack Clubbers have determined that this is almost definitely
         | a bug in Google Workspace where you can create a new Workspace
         | with any g.co subdomain and get it to send some emails without
         | verifying that you own the domain.
         | 
         | Seems like this is the flow:
         | 
         | 1. Create a Google Workspace with a g.co subdomain. Apparently
         | this is not verified, or verifying the domain is not necessary
         | for the next steps.
         | 
         | 2. Create an account for the victim under this Google
         | Workspace.
         | 
         | 3. Reset that account's password.
         | 
         | The victim gets an email from Google Workspace informing them
         | that their password was reset. And this email is a real,
         | legitimate (not spoofed) email from Google because it's just a
         | result of the normal password reset process for a Google
         | Workspace account.
        
       | yread wrote:
       | The business/answers page with the number is about calls from
       | Google Assistant and (now?) explicitly says it's not about calls
       | from the support. That would be this page
       | 
       | https://support.google.com/business/answer/6212928?hl=en
       | 
       | Disappointingly, it only says how to identify automated calls
       | from Google, it doesn't offer a protocol for verifying actual
       | humans from Google calling you. Perhaps it happens so rarely you
       | can just assume it's not Google.
        
       | internetter wrote:
       | To all the people criticizing OP, 5 million people are victims of
       | phishing attacks every year. This attack is more sophisticated
       | than 99.99% of them. Cut OP some slack.
        
         | quickthrowman wrote:
         | > I asked if I could call back a phone number listed on
         | Google.com and she said sure - this number is listed on
         | google.com and you can call back with your case number, but
         | there may be a wait on hold and I might get a different agent.
         | I googled it and sure enough, it was listed on google.com
         | pages. _I didn 't call back though._
         | 
         | Emphasis mine.
         | 
         | Also, if a human called me and claimed to be working for
         | Google, I would laugh heartily and hang up the phone. Google
         | doesn't even have call in tech support, why would they call
         | _you_ for something as banal as a compromised account?
        
           | superq wrote:
           | Admitting one mistake doesn't moot the whole incident, nor
           | does it take Google off the hook.
        
           | internetter wrote:
           | Again, 5 million people fall for phishing. This attack was
           | magnitudes more sophisticated than most. I still get the
           | occasional Nigerian prince scam. They still send them because
           | it still works. Not all of the people who fall for this are
           | stupid. Surely you've made mistakes before.
        
         | nejsjsjsbsb wrote:
         | I agree. Easy to Monday morning quarterback opsec but we're
         | human and the best fall for stuff all the time.
         | 
         | A non tech person wouldn't know Google has bad support and is
         | unlikely to call you, that a number and email can be spoofed,
         | etc. And even if 99% didn't fall for it, just 100 calls gets
         | the scammer a victim on average.
        
       | throwpoaster wrote:
       | URL shorteners are a massive security hazard.
        
         | gruez wrote:
         | Maybe, but in this particular case the attack has nothing to do
         | with url shortening. The essential elements were google
         | assistant (to spoof caller ID), and google workspace (to send
         | the "case" email).
        
       | hombre_fatal wrote:
       | The biggest scare I've gotten is somehow ending up on
       | "colnbase.com" (instead of "coinbase.com").
       | 
       | It's defunct now, but at the time it was a 1:1 replica of
       | Coinbase. And the only reason I noticed was because 1Password
       | didn't offer to fill in my credentials.
       | 
       | While knowing someone's email/password combo might not be enough
       | for an attacker to do anything malicious on Coinbase itself (due
       | to email re-verification maybe), the point is that even the
       | smartest of us Hacker News users can fall for it. And that should
       | scare the rest of us.
        
         | gleenn wrote:
         | So so true. 1Password refusing to auto fill a password has
         | saved me multiple times in the past! Also, one of my friends
         | has a PhD in literally rocket science (aeronautical engineering
         | from MIT) and got scammed by someone who stole his brother's
         | SIM card and did some shenanigans. No one is safe, no matter
         | how smart or tech savvy you think you are! For the less tech
         | savvy folks, I understand why they are scared, it's hard to
         | give them even general tips to not lose the farm to fraudsters.
        
       | ElijahLynn wrote:
       | How is call spoofing allowed by telcos? Is it a technical
       | limitation that let's this happen?
        
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       (page generated 2025-01-24 23:00 UTC)