Stack-based buffer overflow in the GD extension in PHP before 5.2.15 and 5.3.x before 5.3.4 allows context-dependent attackers to cause a denial of service (application crash) via a large number of anti-aliasing steps in an argument to the imagepstext function.
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11939
http://www.securityfocus.com/bid/45338
http://www.php.net/ChangeLog-5.php
http://seclists.org/fulldisclosure/2010/Dec/180