Security problems with sudo

[John Tapsell]

2009/5/17 Thiago Macieira <thiago at kde.org>:
> John Tapsell wrote:
>>2009/5/17 Thiago Macieira <thiago at kde.org>:
>>> John Tapsell wrote:
>>>>  Now the question is..  is there any way to protected against this?
>>>
>>> No. If your environment is already infected, your using of sudo gives
>>> the privilege elevation.
>>>
>>> If you want to protect against that, don't elevate privileges using
>>> sudo. Use ssh -Y.
>>
>>How would that work?  If you run ssh locally, you have the same
>>problems.  A program could simply run a key logger.  If you run
>>remotely but ssh in as the user first, then you have the same problem.
>> If you run remotely and ssh in directly as root, then that goes
>>against the usual restriction to prevent remote root login.
>
> I think ssh-askpass grabs the keyboard, which means it won't work if
> something else grabbed the keyboard.

Okay so the evil problem simply supplies their own ssh-askpass
program, installed to the users home directory, and modifies .bashrc
to add that directory to the front of the path.

> --
>  Thiago Macieira  -  thiago (AT) macieira.info - thiago (AT) kde.org
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