gstreamer-plugins-base: Out-of-bounds heap read in html_context_handle_element

The htmlcontexthandleelement function in gst/subparse/samiparse.c in gst-plugins-base in GStreamer before 1.10.3 allows remote attackers to cause a denial of service out-of-bounds write via a crafted SMI file, as demonstrated by OneNoteManager.smi...