The xmlreader in libxml allows remote attackers to cause a denial of service (memory consumption) via crafted XML data, related to an XML Entity Expansion (XEE) attack.
https://support.apple.com/HT206169
https://support.apple.com/HT206168
https://support.apple.com/HT206167
https://support.apple.com/HT206166
https://security.gentoo.org/glsa/201701-37
https://security.gentoo.org/glsa/201507-08
https://git.gnome.org/browse/libxml2/commit/?id=213f1fe0d76d30eaed6e5853057defc43e6df2c9
http://www.ubuntu.com/usn/USN-2812-1
http://www.securitytracker.com/id/1034243
http://www.securityfocus.com/bid/75570
http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html
http://www.oracle.com/technetwork/topics/security/bulletinoct2015-2511968.html
http://www.debian.org/security/2015/dsa-3430
http://rhn.redhat.com/errata/RHSA-2015-2550.html
http://rhn.redhat.com/errata/RHSA-2015-1419.html
http://lists.opensuse.org/opensuse-updates/2016-01/msg00031.html
http://lists.opensuse.org/opensuse-updates/2015-12/msg00120.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-November/172943.html
http://lists.fedoraproject.org/pipermail/package-announce/2015-November/172710.html
http://lists.apple.com/archives/security-announce/2016/Mar/msg00004.html
http://lists.apple.com/archives/security-announce/2016/Mar/msg00002.html
http://lists.apple.com/archives/security-announce/2016/Mar/msg00001.html
http://lists.apple.com/archives/security-announce/2016/Mar/msg00000.html