The process_frame_obj function in sanm.c in libavcodec in FFmpeg before 1.2.1 does not validate width and height values, which allows remote attackers to cause a denial of service (integer overflow, out-of-bounds array access, and application crash) via crafted LucasArts Smush video data.
http://git.videolan.org/?p=ffmpeg.git%3Ba=commit%3Bh=9dd04f6d8cdd1c10c28b2cb4252c1a41df581915
http://git.videolan.org/?p=ffmpeg.git%3Ba=commit%3Bh=524d0d2cfc7bab1b348f85e7c0369859e63781cf