oss-sec mailing list archives
Re: CVE request - mcrypt buffer overflow flaw
From: Raphael Geissert <geissert () debian org>
Date: Thu, 6 Sep 2012 15:11:27 -0500
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, -- Raphael Geissert - Debian Developer www.debian.org - get.debian.net
Attachment:
mcrypt-format-strings.patch
Description:
Attachment:
CVE-2012-4409.patch
Description:
Current thread:
- CVE request - mcrypt buffer overflow flaw Vincent Danen (Sep 06)
- Re: CVE request - mcrypt buffer overflow flaw Kurt Seifried (Sep 06)
- Re: CVE request - mcrypt buffer overflow flaw Raphael Geissert (Sep 06)
- Re: CVE request - mcrypt buffer overflow flaw Vincent Danen (Sep 06)
- Re: CVE request - mcrypt buffer overflow flaw Raphael Geissert (Sep 10)
- Re: CVE request - mcrypt buffer overflow flaw Kurt Seifried (Sep 13)
- Re: CVE request - mcrypt buffer overflow flaw Vincent Danen (Sep 06)
- Re: CVE request - mcrypt buffer overflow flaw Eygene Ryabinkin (Sep 11)
- Re: CVE request - mcrypt buffer overflow flaw Raphael Geissert (Sep 12)
- Re: CVE request - mcrypt buffer overflow flaw Kurt Seifried (Sep 13)
- Re: CVE request - mcrypt buffer overflow flaw Raphael Geissert (Sep 13)
- Re: CVE request - mcrypt buffer overflow flaw Raphael Geissert (Sep 12)
- Re: CVE request - mcrypt buffer overflow flaw Raphael Geissert (Sep 15)