It was discovered that libxml2, a library providing support to read, modify and write XML files, incorrectly performs entity substituton in the doctype prolog, even if the application using libxml2 disabled any entity substitution. A remote attacker could provide a specially-crafted XML file that, when processed, would lead to the exhaustion of CPU and memory resources or file descriptors.
This issue was discovered by Daniel Berrange of Red Hat.
Upstream patch: https://git.gnome.org/browse/libxml2/commit/?id=9cd1c3cfbd32655d60572c0a413e017260c854df
Red Hat bug: https://bugzilla.redhat.com/show_bug.cgi?id=1090976
-- Stefan Cornelius / Red Hat Security Response Team