Buffer overflow in Apple QuickTime before 7.7.4 allows remote attackers to execute arbitrary code or cause a denial of service (application crash) via a crafted movie file with H.263 encoding.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A16497
http://support.apple.com/kb/HT5770
http://lists.apple.com/archives/security-announce/2013/May/msg00001.html