The iff_read_header function in iff.c in libavformat in FFmpeg through 1.1.3 does not properly handle data sizes for Interchange File Format (IFF) data during operations involving a CMAP chunk or a video codec, which allows remote attackers to cause a denial of service (integer overflow, out-of-bounds array access, and application crash) or possibly have unspecified other impact via a crafted header.
http://www.ubuntu.com/usn/USN-1790-1
http://git.videolan.org/?p=ffmpeg.git%3Ba=commit%3Bh=3dbc0ff9c3e6f6e0d08ea3d42cb33761bae084ba