Double free vulnerability in the mpeg_decode_frame function in libavcodec/mpeg12.c in FFmpeg before 0.11, and Libav 0.7.x before 0.7.7 and 0.8.x before 0.8.5, has unknown impact and attack vectors, related to resetting the data size value.
ffmpeg.org/security.html
git.videolan.org/?p=ffmpeg.git%3Ba=commitdiff%3Bh=951cbea56fdc03ef96d07fbd7e5bed755d42ac8a
libav.org/releases/libav-0.7.7.changelog
libav.org/releases/libav-0.8.5.changelog
secunia.com/advisories/50468
www.openwall.com/lists/oss-security/2012/08/31/3
www.openwall.com/lists/oss-security/2012/09/02/4
www.securityfocus.com/bid/55355
www.ubuntu.com/usn/USN-1705-1
www.ubuntu.com/usn/USN-1706-1