The sse2_composite_src_x888_8888 function in Pixman, as used in Cairo in Mozilla Firefox 28.0 and SeaMonkey 2.25 on Windows, allows remote attackers to execute arbitrary code or cause a denial of service (out-of-bounds write and application crash) by painting on a CANVAS element.
https://bugzilla.mozilla.org/show_bug.cgi?id=963962
http://www.ubuntu.com/usn/USN-2185-1
http://www.securitytracker.com/id/1030164
http://www.securitytracker.com/id/1030163
http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html
http://www.mozilla.org/security/announce/2014/mfsa2014-41.html
http://secunia.com/advisories/59866
http://lists.opensuse.org/opensuse-updates/2014-05/msg00033.html
http://lists.opensuse.org/opensuse-updates/2014-05/msg00010.html
http://lists.fedoraproject.org/pipermail/package-announce/2014-May/132437.html