Bypassing Google's Two-Factor Authentication

An anonymous reader writes "The team at Duo Security figured out how to bypass Google's two-factor authentication, abusing Google's application-specific passwords. Curiously, this means that application-specific passwords are actually more powerful than users' regular passwords, as they can be used to disable the second factor entirely to gain control of an account. Duo [publicly released this exploit Monday] after Google fixed this last week — seven months after initially replying that this was expected behavior!"

Comments

Re:Nice Guys!

[Anonymous Coward]

The generally accepted behavior is to:

1. Report the bug to the developers.
2. Work out a disclosure timeline and give them time to fix the problem.
3. Disclose after the fix is released.

Except when the developer at stage two says; 'that's not a bug' or, 'that's intended design', or FOAD' or they ignore you completely. Then the responsible thing is to disclose the bug so that everyone knows that it is an issue and stops using the service until the developer is forced to address the issue.

In this case, Google said that it was by design. Meaning essentially that there was no fault/bug when there clearly was. At that point, with no expectation of it being fixed, Duo Security would have been well within the right to disclose and force Google's hand. Or, they could turn evil and profit from the exploit, since you seem to feel that they should not have disclosed a bug that Google was ignoring.

Re:Where's the surprise?

[Talennor]

It's a privilege escalation problem. The surprise was that changing your main password or password recovery email should be only done by the full account, not an ASP context.