libavcodec/h264.c in FFmpeg before 0.11.4 allows remote attackers to cause a denial of service (crash) via vectors related to alternating bit depths in H.264 data.
http://www.ffmpeg.org/security.html
http://git.videolan.org/?p=ffmpeg.git%3Ba=commit%3Bh=072be3e8969f24113d599444be4d6a0ed04a6602