ruby is vulnerable to XML Entity Expansion (XEE) attacks. The vulnerability exists as the REXML parser in Ruby 1.9.x before 1.9.3-p550, 2.0.x before 2.0.0-p594, and 2.1.x before 2.1.4 allows remote attackers to cause a denial of service (memory consumption) via a crafted XML document, aka an XML Entity Expansion (XEE) attack.
advisories.mageia.org/MGASA-2014-0443.html
lists.apple.com/archives/security-announce/2015/Sep/msg00008.html
lists.opensuse.org/opensuse-updates/2014-12/msg00035.html
lists.opensuse.org/opensuse-updates/2015-01/msg00000.html
lists.opensuse.org/opensuse-updates/2015-01/msg00004.html
rhn.redhat.com/errata/RHSA-2014-1911.html
rhn.redhat.com/errata/RHSA-2014-1912.html
rhn.redhat.com/errata/RHSA-2014-1913.html
rhn.redhat.com/errata/RHSA-2014-1914.html
secunia.com/advisories/61607
secunia.com/advisories/62050
secunia.com/advisories/62748
www.debian.org/security/2015/dsa-3157
www.debian.org/security/2015/dsa-3159
www.mandriva.com/security/advisories?name=MDVSA-2015:129
www.oracle.com/technetwork/topics/security/linuxbulletinjan2016-2867209.html
www.securityfocus.com/bid/70935
www.ubuntu.com/usn/USN-2397-1
access.redhat.com/security/updates/classification/#moderate
rhn.redhat.com/errata/RHSA-2014-1911.html
support.apple.com/HT205267
www.ruby-lang.org/en/news/2014/10/27/rexml-dos-cve-2014-8080/