Openwall GNU/*/Linux - a small security-enhanced Linux distro for servers
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Thu, 13 Sep 2012 14:48:00 -0600
From: Kurt Seifried <kseifried@...hat.com>
To: oss-security@...ts.openwall.com
CC: Raphael Geissert <geissert@...ian.org>
Subject: Re: CVE request - mcrypt buffer overflow flaw

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 09/06/2012 02:11 PM, Raphael Geissert wrote:
> Hi,
> 
> On Thursday 06 September 2012 09:37:14 Vincent Danen wrote:
>> A buffer overflow was reported [1],[2] in mcrypt version 2.6.8
>> and earlier due to a boundary error in the processing of an
>> encrypted file (via the check_file_head() function in
>> src/extra.c).  If a user were tricked into attempting to decrypt
>> a specially-crafted .nc encrypted flie, this flaw would cause a
>> stack-based buffer overflow that could potentially lead to
>> arbitrary code execution.
> 
> I'm attaching a patch that makes mcrypt abort when the salt is
> longer than the temp buffer it uses.
> 
> While working on it, I noticed the err_ functions do not have a
> constant printf format, yet there are calls such as: 
> sprintf(tmperr, _("Input File: %s\n"), infile); err_info(tmperr); 
> [print_enc_info in src/extra.c]
> 
> And a few others in src/mcrypt.c; for instance: $ mcrypt
> --no-openpgp "%s.nc" mcrypt: h���Fn�`.nc is not a regular file.
> Skipping...
> 
> I'm attaching another patch that prevents the format string
> attacks.
> 
> Cheers,

Please use CVE-2012-4426 for these format string issues.

- -- 
Kurt Seifried Red Hat Security Response Team (SRT)
PGP: 0x5E267993 A90B F995 7350 148F 66BF 7554 160D 4553 5E26 7993

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://www.enigmail.net/
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=G+yt
-----END PGP SIGNATURE-----

Powered by blists - more mailing lists

Your e-mail address:

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.