libavcodec/pngdec.c in FFmpeg before 2.4.2 accepts the monochrome-black format without verifying that the bits-per-pixel value is 1, which allows remote attackers to cause a denial of service (out-of-bounds access) or possibly have unspecified other impact via crafted PNG data.
https://security.gentoo.org/glsa/201603-06
http://www.ffmpeg.org/security.html
http://git.videolan.org/?p=ffmpeg.git%3Ba=commit%3Bh=3e2b745020c2dbf0201fe7df3dad9e7e0b2e1bb6