Slashdot Mirror


Academics Claim Google Android 2FA Is Breakable (theregister.co.uk)

totalcaos writes: Attackers who control the [browser on the] PC of a user consuming Google services (Gmail, Google+ etc) can surreptitiously push and activate apps on the user's mobile device, bypassing SMS-based two-factor authentication (2FA) via the phone. How Anywhere Computing Just Killed Your Phone-Based Two-Factor Authentication is a paper that explains the wider issues of phone-based 2FA. Herbert Boss, professor of systems and security at Vrije Unversiteit Amsterdam, who co-authored the mobile security paper with the two PhD students, disclosed the vulnerability to Google but they "still [refuse] to fix it."

4 of 48 comments (clear)

  1. Re:Interesting but not sure how 'practical' it is by SmilingBoy · · Score: 3, Interesting

    Apparently it is not possible. See http://stackoverflow.com/quest... - "This code requires the activity to be in memory and in the foreground. Without root access and without modifying Android's source there is no way you can one can take a screenshot."

  2. Re:Fixable by phone-side installation prompt by chill · · Score: 5, Interesting

    If the your main PC that is used to control your Google accounts, including permissions, is under the control of bad actors, you're screwed either way.

    They could always just turn off 2FA from the PC.

    This paper is akin to bitching if someone got a hold of my phone in my home, where location based trust is used and keeps the phone unlocked, then the bad actor could install stuff then.

    Duh!

    It is next to impossible to ensure security if the bad guys have control of the actual hardware.

    P.S. -- You misunderstood the premise of the person you were replying to. They are saying turn on 2FA for accessing your Google accounts ON THE PC. That way you need control of not only the PC, but the phone as well to essentially get control. Perfect? No. A much bigger hurdle? Yes.

    --
    Learning HOW to think is more important than learning WHAT to think.
  3. Re:Fixable by phone-side installation prompt by msauve · · Score: 5, Interesting

    I think you missed the point of the GP - Google also support s 2FA for the PC web browser, which requires you have the phone in order to complete the sign on. The authors say they "assume that the attacker already has control over the victim's PC," but that's not right. They assume that they not only have the PC, but a running browser which the user left logged into Google services. The paper just glosses over this.

    Simply having access to someone's PC and Google credentials is not enough if they have turned 2FA on for the web, they would also need the phone to complete the sign on on the PC. If they have control of both factors (name/password and phone), it is not a failure of 2FA, that's exactly how 2FA is intended to work. And, if you're going to base a claim on such a poor premise, why not simply premise it on the attacker having the phone itself, already logged into Google services, which makes the whole thing even easier?

    This is a very poor paper. Having started with that faulty premise, they go on through a bunch of stuff which simply doesn't matter. Perhaps I'll write a similar paper about how water is wet. I'll also point out that the paper also claims a similar vulnerability for Apple's iOS, which the summary ignores. That seems pointedly biased.

    --
    "National Security is the chief cause of national insecurity." - Celine's First Law
  4. Uhh... by The+MAZZTer · · Score: 3, Interesting

    Nobody's beaten Google's 2FA. Remote install does not REQUIRE 2FA. If Google should decide it does, they can throw up a prompt for a code when you go to do a remote install and suddenly the "vulnerability" is gone. I agree with the article as much as they might want to do this. Right now Google uses 2FA for login and protecting account security settings only.

    It's important to note that an attacker would already have to be logged in as a user. If a user keeps themselves logged into an insecure PC an attacker can use there's only so much Google can do... the article doesn't really mention the attacker has access to much of the user's Google services and data in addition to remote install. It brings to mind the "It rather involved being on the other side of this airtight hatchway" class of "vulnerability" that Raymond Chen bases off a quote from The Hitchhiker's Guide.

    In addition there's a couple problems not addressed in the link I can see. First of all, AFAIK, other than on a really old version of Android through a glitch, any newly installed app cannot run any code until the first time the user launches it. Then it is allowed to install background services and whatever. But not before then. So if you manage to silently install an app which the user never sees or runs you've defeated yourself. Secondly, this can only be used to install apps from Google Play, which Google can manage to take down malicious apps as they are reported.