oggparsevorbis.c in FFmpeg 0.5 does not properly perform certain pointer arithmetic, which might allow remote attackers to obtain sensitive memory contents and cause a denial of service via a crafted file that triggers an out-of-bounds read.
http://scarybeastsecurity.blogspot.com/2009/09/patching-ffmpeg-into-shape.html
http://secunia.com/advisories/36805
http://secunia.com/advisories/38643
http://secunia.com/advisories/39482
http://www.debian.org/security/2010/dsa-2000
http://www.mandriva.com/security/advisories?name=MDVSA-2011:060
http://www.mandriva.com/security/advisories?name=MDVSA-2011:061
http://www.mandriva.com/security/advisories?name=MDVSA-2011:088
http://www.mandriva.com/security/advisories?name=MDVSA-2011:112
http://www.mandriva.com/security/advisories?name=MDVSA-2011:114
http://www.ubuntu.com/usn/USN-931-1