Memory leak in the poolGrow function in expat/lib/xmlparse.c in expat before 2.1.0 allows context-dependent attackers to cause a denial of service (memory consumption) via a large number of crafted XML files that cause improperly-handled reallocation failures when expanding entities.
https://support.apple.com/HT205637
http://www.ubuntu.com/usn/USN-1613-2
http://www.ubuntu.com/usn/USN-1613-1
http://www.ubuntu.com/usn/USN-1527-1
http://www.securitytracker.com/id/1034344
http://www.securityfocus.com/bid/52379
http://www.mandriva.com/security/advisories?name=MDVSA-2012:041
http://www.debian.org/security/2012/dsa-2525
http://sourceforge.net/tracker/?func=detail&atid=110127&aid=2958794&group_id=10127
http://sourceforge.net/projects/expat/files/expat/2.1.0/
http://secunia.com/advisories/51040
http://secunia.com/advisories/51024
http://secunia.com/advisories/49504
http://rhn.redhat.com/errata/RHSA-2016-2957.html
http://rhn.redhat.com/errata/RHSA-2016-0062.html
http://rhn.redhat.com/errata/RHSA-2012-0731.html
http://lists.apple.com/archives/security-announce/2015/Dec/msg00005.html
http://expat.cvs.sourceforge.net/viewvc/expat/expat/lib/xmlparse.c?r1=1.166&r2=1.167