PHP Use After Free Vulnerability - CVE-2015-6831
Multiple use-after-free vulnerabilities in SPL in PHP before 5.4.44 5.5.x before 5.5.28 and 5.6.x before 5.6.12 allow remote attackers to execute arbitrary code via vectors involving (1) ArrayObject (2) SplObjectStorage and (3) SplDoublyLinkedList which are mishandled during unserialization.