The Gst.MapInfo function in Vala 0.26.0 and 0.26.1 uses an incorrect buffer length declaration for the Gstreamer bindings, which allows context-dependent attackers to cause a denial of service (crash) or possibly execute arbitrary code via unspecified vectors, which trigger a heap-based buffer overflow.
https://bugzilla.redhat.com/show_bug.cgi?id=1181404
https://bugzilla.redhat.com/show_bug.cgi?id=1177840
http://lists.opensuse.org/opensuse-updates/2015-01/msg00069.html