The ff_combine_frame function in libavcodec/parser.c in FFmpeg before 2.1 does not properly handle certain memory-allocation errors, which allows remote attackers to cause a denial of service (out-of-bounds array access) or possibly have unspecified other impact via crafted data.
https://security.gentoo.org/glsa/201603-06
http://openwall.com/lists/oss-security/2013/12/08/3