Integer signedness error in the add_bytes_l2_c function in libavcodec/pngdsp.c in FFmpeg before 2.1 allows remote attackers to cause a denial of service (out-of-bounds array access) or possibly have unspecified other impact via crafted PNG data.
https://trac.ffmpeg.org/ticket/2919
https://security.gentoo.org/glsa/201603-06
http://www.debian.org/security/2014/dsa-2855
http://openwall.com/lists/oss-security/2013/12/08/3
http://openwall.com/lists/oss-security/2013/11/26/7
http://git.libav.org/?p=libav.git%3Ba=blob%3Bf=Changelog%3Bhb=refs/tags/v9.11