(1) Zend_Dom, (2) Zend_Feed, (3) Zend_Soap, and (4) Zend_XmlRpc in Zend Framework 1.x before 1.11.13 and 1.12.x before 1.12.0 allow remote attackers to cause a denial of service (CPU consumption) via recursive or circular references in an XML entity definition in an XML DOCTYPE declaration, aka an XML Entity Expansion (XEE) attack.