Improper Restriction of XML External Entity Reference
Zend_XmlRpc in Zend Framework 1.x before 1.11.12, 1.12.x before 1.12.0 and 2.x before 2.0.0rc2 does not properly handle SimpleXMLElement classes, which allows remote attackers to read arbitrary files or create TCP connections via an external entity reference in a DOCTYPE element in an XML-RPC request, aka an XML external entity (XXE) injection attack.
CWE-611 - Improper Restriction of XML External Entity Reference
Listed 4th in the 'OWASP Top Ten', XML External Entities (XXE) vulnerability allows attackers to provide an XML input that contains an external entity. When the XML is parsed, it can cause data extraction and manipulation, execution of commands, denial-of-service attacks, and server-side request forgery.