The REXML parser in Ruby 1.9.x before 1.9.3 patchlevel 551, 2.0.x before 2.0.0 patchlevel 598, and 2.1.x before 2.1.5 allows remote attackers to cause a denial of service (CPU and memory consumption) a crafted XML document containing an empty string in an entity that is used in a large number of nested entity references, aka an XML Entity Expansion (XEE) attack. NOTE: this vulnerability exists because of an incomplete fix for CVE-2013-1821 and CVE-2014-8080.<a href=http://cwe.mitre.org/data/definitions/611.html target=_blank>CWE-611: Improper Restriction of XML External Entity Reference ('XXE')</a>
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2014-8090
