The mov_read_dref function in libavformat/mov.c in Libav before 11.7 and FFmpeg before 0.11 allows remote attackers to cause a denial of service (memory corruption) or execute arbitrary code via the entries value in a dref box in an MP4 file.
https://security.gentoo.org/glsa/201705-08
https://libav.org/releases/libav-11.7.changelog
https://github.com/FFmpeg/FFmpeg/commit/689e59b7ffed34eba6159dcc78e87133862e3746
https://git.libav.org/?p=libav.git%3Ba=commit%3Bh=7e01d48cfd168c3dfc663f03a3b6a98e0ecba328
https://ffmpeg.org/security.html
https://bugzilla.libav.org/show_bug.cgi?id=929
http://www.debian.org/security/2016/dsa-3603
http://lists.opensuse.org/opensuse-updates/2016-06/msg00105.html