The htmlParseComment function in HTMLparser.c in libxml2 allows attackers to obtain sensitive information, cause a denial of service (out-of-bounds heap memory access and application crash), or possibly have unspecified other impact via an unclosed HTML comment.
rhn.redhat.com/errata/RHSA-2016-1089.html
www.debian.org/security/2015/dsa-3430
www.openwall.com/lists/oss-security/2015/04/19/4
www.openwall.com/lists/oss-security/2015/09/13/1
www.openwall.com/lists/oss-security/2015/12/31/7
www.securityfocus.com/bid/79811
bugzilla.gnome.org/show_bug.cgi?id=746048
git.gnome.org/browse/libxml2/commit/?id=e724879d964d774df9b7969fc846605aa1bac54c
hackerone.com/reports/57125#activity-384861