Integer overflow in the vp3_dequant function in the VP3 decoder (vp3.c) in libavcodec in FFmpeg 0.5.x before 0.5.7, 0.6.x before 0.6.4, 0.7.x before 0.7.9, and 0.8.x before 0.8.8; and in Libav 0.5.x before 0.5.6, 0.6.x before 0.6.4, and 0.7.x before 0.7.3 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a crafted VP3 stream, which triggers a buffer overflow.
http://www.securityfocus.com/archive/1/520622
http://www.mandriva.com/security/advisories?name=MDVSA-2012:076
http://www.mandriva.com/security/advisories?name=MDVSA-2012:075
http://www.mandriva.com/security/advisories?name=MDVSA-2012:074
http://ubuntu.com/usn/usn-1333-1
http://ubuntu.com/usn/usn-1320-1
http://libav.org/releases/libav-0.7.3.changelog
http://libav.org/releases/libav-0.6.4.changelog
http://libav.org/releases/libav-0.5.6.changelog
http://git.videolan.org/?p=ffmpeg.git%3Ba=commit%3Bh=eef5c35b4352ec49ca41f6198bee8a976b1f81e5
http://git.libav.org/?p=libav.git%3Ba=commit%3Bh=8b94df0f2047e9728cb872adc9e64557b7a5152f