Zend Framework 1 (ZF1) before 1.12.4, Zend Framework 2 before 2.1.6 and 2.2.x before 2.2.6, ZendOpenId, ZendRest, ZendService_AudioScrobbler, ZendService_Nirvanix, ZendService_SlideShare, ZendService_Technorati, and ZendService_WindowsAzure before 2.0.2, ZendService_Amazon before 2.0.3, and ZendService_Api before 1.0.0 allow remote attackers to cause a denial of service (CPU consumption) via (1) recursive or (2) circular references in an XML entity definition in an XML DOCTYPE declaration, aka an XML Entity Expansion (XEE) attack. NOTE: this issue exists because of an incomplete fix for CVE-2012-6532.