Onderwerp: Re: [Full-Disclosure] Re: Gaim festival plugin exploit

>
> DUH... would help if I attached my attachment.
>
> I am right proud of myself for this, and it also needs mention to
> address the security issue that our friend Error (is that a reference to
> Zelda 2?) raised.
>
> Attached, find the latest reissue of the Gaim festival plugin. The guy
> that wrote it, wrote it for pre-0.68 Perl API, but it was secure against
> the sort of attack that Error described. I have since taken it and
> recoded it to work with post-0.68 versions of Gaim. It is attached. By
> all means, if you see an exploitable bug in there, let me know! I'm
> just a perl-tot..

Hi Brian,

This updated version is still vulnerable. You should be *very* wary of
any call to system() or fork(). Consider this input:

"This is only a test && rm -rf /"

Notice that ';' isn't the only way to inject into a commandline.

Cheers,

Cael

>>>>> "HCTITS" == HCTITS Security Division <security@humancentrictech.com> writes:

HCTITS> DUH... would help if I attached my attachment.

Is this is repeat? I'm going to repeat myself then.

YOUR FIX DOES NOT HELP. Please use my posted fix.

>> system("echo \"$string\" | /usr/bin/festival --tts");

Replace this with

open FEST, "|/usr/bin/festival --tts";
print FEST $string, "\n";
close FEST;

No shells involved. Only DOS exploits and maybe the usual
C-language overflows in festival itself.

--
Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095
<merlyn@stonehenge.com> <URL:http://www.stonehenge.com/merlyn/>
Perl/Unix/security consulting, Technical writing, Comedy, etc. etc.
See PerlTraining.Stonehenge.com for onsite and open-enrollment Perl training!