The filter_frame function in libavfilter/vf_fps.c in FFmpeg before 2.1 does not properly ensure the availability of FIFO content, which allows remote attackers to cause a denial of service (double free) 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