Sudo & su

[Vivek J. Patankar]

Rik van Riel wrote:
> On Sat, 3 Nov 2007 18:22:16 -0500 (CDT)
> "Chris St. Pierre" <stpierre at NebrWesleyan.edu> wrote:
> 
>> On Sat, 3 Nov 2007, Carville, Stephen wrote:
> 
>>> Do not give it all then try to deny certain commands.  Any reasonably smart use
>>> can defeat that.  Start with nothing and allow only what is necessary.
>> This is _excellent_ advice.
>>
>> Let's say you give someone sudo but don't allow them to run 'su'.  I
>> can think of half a dozen ways off the top of my head to get around
>> that:
>>
>> 'sudo bash'; run su
>> 'sudo screen'; run su
>> 'sudo emacs'; M-x shell; run su
>> 'sudo script su'
>> Write a shell script that invokes su and run it with sudo
>> 'true | sudo xargs su'
>>
>> That was after about 30 seconds of thought.  A dedicated attacker
>> could find significantly more avenues of attack.
> 
> less, vi and a number of other innocent looking programs
> can be used to invoke a shell.
> 
> Of course, if you can sudo vi, you could just edit the
> sudoers file.
> 
> Stephen's advice is to be taken seriously.

Thanks everybody, for all the good advise.

-- 
Regards,
विवेक ज. पाटणकर (Vivek J. Patankar)

Registered Linux User #374218
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