Unspecified vulnerability in the vc1_decode_frame function in libavcodec/vc1dec.c in FFmpeg before 0.11 and Libav 0.8.x before 0.8.4 has unknown impact and attack vectors, related to inconsistencies in "coded slice positions and interlacing" that trigger "out of array writes."
http://www.securityfocus.com/bid/55355
http://www.openwall.com/lists/oss-security/2012/09/02/4
http://www.openwall.com/lists/oss-security/2012/08/31/3
http://www.mandriva.com/security/advisories?name=MDVSA-2013:079
http://secunia.com/advisories/51257
http://secunia.com/advisories/50468
http://libav.org/releases/libav-0.8.4.changelog
http://git.videolan.org/?p=ffmpeg.git%3Ba=commitdiff%3Bh=5e59a77cec804a9b44c60ea22c17beba6453ef23