CVE 2017-16840
The VC-2 Video Compression encoder in FFmpeg 3.0 and 3.4 allows remote attackers to cause a denial of service (out-of-bounds read) because of incorrect buffer padding for non-Haar wavelets, related to libavcodec/vc2enc.c and libavcodec/
See the 
CVE page on Mitre.org
for more details.
