Buffer underflow in X.org libXvMC before 1.0.10 allows remote X servers to have unspecified impact via an empty string.
https://security.gentoo.org/glsa/201704-03
https://lists.x.org/archives/xorg-announce/2016-October/002720.html
https://cgit.freedesktop.org/xorg/lib/libXvMC/commit/?id=2cd95e7da8367cccdcdd5c9b160012d1dec5cbdb
http://www.securitytracker.com/id/1036945
http://www.securityfocus.com/bid/93371