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I know someone whose 2-factor phone authentication was hacked...

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Re: I know someone whose 2-factor phone authentication was hacked...

#21
post #3

I use the Google Authenticator app, which makes the token only available to that specific device, rather than through SMS. This gets around the problem of cloning a phone number. iOS: http://itunes.apple.com/us/app/google-authenticator/id388497... Android: https://play.google.com/store/apps/details?id=com.google.and...

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Re: I know someone whose 2-factor phone authentication was hacked...

#22
post #7
post #6

Earlier quoted context omitted.

Does the app notify you when authentication is attempted? The reason I still use SMS is that I will instantly get notified if someone has my password and attempts to access my account.

I was worried about someone getting into my account so I made this: http://blog.jgc.org/2011/06/my-email-canary.html

Whilst a cunning idea if it catches some unsophisticated crook who just dives in and starts looking for goodies, I'd expect that it's common enough knowledge (e.g. image-bugs dropped in spam to check account liveness) that a serious attacker would either slurp your account via IMAP/POP and browse with external resource loading disabled, or just enable that setting in your gmail account itself, which exists for exactly the reason mentioned above.

The main improvement I can see you've made is that it's real-time enough that you should be able to jump on it straight away and do something rather than the batch processes I suspect spammers use.

There was a cunning|creepy trick used by Facebook I recall reading about not that long ago[1] that relied on Outlook autoloading bgsound attributes despite image loading settings, but I don't know of any comparable holes in gmail.

[1] http://pandodaily.com/2012/03/06/facebook-knows-when-you-ope...

Re: I know someone whose 2-factor phone authentication was hacked...

#23

Two factor authentication is still, in my opinion, the strongest way to go. This case is really the phone company's fault, maybe they'll learn from this and start teaching the customer support reps what the difference is between a correct password and an incorrect password.

Luckily for Gmail, its virtually impossible to call anyone at Google. Maybe all the talk of "Gmail's lack of support" is actually a security feature :)

This isn't true. Phone support is provided for domain administrators of paying apps customers.

http://support.google.com/a/bin/request.py

Re: I know someone whose 2-factor phone authentication was hacked...

#24
post #14

Earlier quoted context omitted.

(TL;DR at bottom) I see a lot of hacks of voice mails and then requests for Google to use the second factor to reset the account...all by baddies. Who then proceed to take over the account. So, it seems to me that it's worse than having no second factor at all. After all, why is it stronger to use two factors than just using a strong password from your laptop or personal devices - without ANY backup contact informati…

2FA using phone calls/SMS is basically lameness (similar to KBA; it protects against huge numbers of users with bad passwords being a vulnerability to the bank, and is a cheap compliance step, but provides no additional security to a targeted victim). Overarching all of this, there's a great opportunity to fix things in the desktop -> mobile transition; desktop OS security is IMO a lost cause, but mobile started from…

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Re: I know someone whose 2-factor phone authentication was hacked...

#26
post #3

I use the Google Authenticator app, which makes the token only available to that specific device, rather than through SMS. This gets around the problem of cloning a phone number. iOS: http://itunes.apple.com/us/app/google-authenticator/id388497... Android: https://play.google.com/store/apps/details?id=com.google.and...

You can still press "don't have your phone?" and send a code through SMS, unless there's a way to disable that.

Re: I know someone whose 2-factor phone authentication was hacked...

#27
I'm a pretty big fan of the rolling token 2-factor authentication model, with the app on your phone presenting you the rolling token. The Blizzard login app is the biggest single example that comes to mind. SMS really isn't secure, I think something like this could be a good next step to phase in.

Re: I know someone whose 2-factor phone authentication was hacked...

#28
post #20
post #3

I use the Google Authenticator app, which makes the token only available to that specific device, rather than through SMS. This gets around the problem of cloning a phone number. iOS: http://itunes.apple.com/us/app/google-authenticator/id388497... Android: https://play.google.com/store/apps/details?id=com.google.and...

I use this too, but I don't think it actually prevents the attack described in the article, at least in my case. When I setup my 2-factor auth for my Google account, I also setup a series of backups in case I lost access to my phone. One of them was my phone number, and another was a phone number of a trusted friend.

It prevents human engineering of the phone company. One might hope that Google would be better at the security implementation (i.e. the BT operator apparently "validated" an incorrect password, which indicates to me that it was a quick hack, probably just a field in the customer record about which the operators weren't trained).

Also: I'd hope that Google wouldn't allow a complete account reset based solely on the backup device. That should be a backup for your second factor only, you should still need the password.

Re: I know someone whose 2-factor phone authentication was hacked...

#29

Two factor authentication is still, in my opinion, the strongest way to go. This case is really the phone company's fault, maybe they'll learn from this and start teaching the customer support reps what the difference is between a correct password and an incorrect password.

(TL;DR at bottom) I see a lot of hacks of voice mails and then requests for Google to use the second factor to reset the account...all by baddies. Who then proceed to take over the account. So, it seems to me that it's worse than having no second factor at all. After all, why is it stronger to use two factors than just using a strong password from your laptop or personal devices - without ANY backup contact informati…

> I see a lot of hacks of voice mails and then requests for Google to use the second factor to reset the account...all by baddies.

(Disclaimer: I work for a telephone and software-based 2factor provider)

If your telephone-based 2 factor authentication is being thwarted by voice mail hacking, the problem lies in the implementation of the phone call itself, not necessarily the method. Unfortunately, certain solutions are built to be "quick and dirty" and just play an automated message that spits out a temporary password 3 times and hangs up. These make it easy for attackers to scrape them out of voice mail boxes.

Properly designed solutions will actually require call affirmation (for example: the user will be asked to press a randomized DTMF digit before a temporary password is spoken). Certain locations (like North America) can take advantage of features like call-forward detection, which can prevent sensitive information from being delivered if a number is determined to be forwarded.

Ultimately, it may not be a silver bullet, but when it's done right you're left with something much more effective than a minimum effort/lowest possible cost approach.

Re: I know someone whose 2-factor phone authentication was hacked...

#30
post #3

I use the Google Authenticator app, which makes the token only available to that specific device, rather than through SMS. This gets around the problem of cloning a phone number. iOS: http://itunes.apple.com/us/app/google-authenticator/id388497... Android: https://play.google.com/store/apps/details?id=com.google.and...

Is it possible that the app runs in sandbox? Or is that already the case?
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