Re: Unfiltered escape sequences in filenames contained in ZIP archives wouldn't be escaped on displaying or logging, and can also lead to bypass AV scanning

["Dr. Peter Bieringer" <pbieringer () aerasec de>]

Hi Michael,

--On Tuesday, March 15, 2005 01:51:55 PM -0600 "Michael J. Pomraning"
<mjp-bugtraq () securepipe com> wrote:

> On Mon, 14 Mar 2005, Dr. Peter Bieringer wrote:
>
> > during investigation of Sober.l we got the idea to replace the spaces of
> > a filename contained in the ZIP archive by some escape sequences.
> [...]
> > Also we found that at least 2 AV scan programs from 2 vendors do not
> > detect the virus inside and report "clean" instead.
>
> I think Sophos passes the test.  I find that the underlying API (as
> exposed by a python wrapper) is able to detect the viruses in all cases.
> For the command line "sweep" utility, try adding the "-all" switch to your
> invocation:
>
>    $ /usr/local/bin/sweep -ss -archive -all
> unfiltered-escape-sequences-in-filename-eicar.zip     >>> Virus
> 'EICAR-AV-Test' found in file
> unfiltered-escape-sequences-in-filename-eicar.zip/Test_[2J_[2;5m_[1;31mHA
> CKER ATTACK_[2;25m_[22;30m_[3q.txt/eicar_com.zip/eicar.com    $ md5sum
> unfiltered-escape-sequences-in-filename-eicar.zip 
>    38363004047dc11b206305bd3660d68f
> unfiltered-escape-sequences-in-filename-eicar.zip
>
> This is using engine 2.28.4, as in your tests.  The consituent filenames
> are escaped before being displayed, too (sadly excepting ASCII BEL).


Thank you for your investigations, we can confirm this. So using "-all"
will solve the problem.

I've updated the advisory.

Regards,
        Peter

-- 
Dr. Peter Bieringer                             Phone: +49-8102-895190
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