The sbr_qmf_synthesis function in libavcodec/aacsbr.c in FFmpeg before 0.9.1 allows remote attackers to cause a denial of service (application crash) via a crafted mpg file that triggers memory corruption involving the v_off variable, probably a buffer underflow.
https://exchange.xforce.ibmcloud.com/vulnerabilities/78934
http://www.openwall.com/lists/oss-security/2012/02/14/4
http://www.openwall.com/lists/oss-security/2012/02/01/11
http://git.videolan.org/?p=ffmpeg.git%3Ba=commit%3Bh=944f5b2779e4aa63f7624df6cd4de832a53db81b