A memory corruption issue exists in QuickTime's handling of Sorenson encoded movie files. Viewing a maliciously crafted movie file may lead to an unexpected application termination or arbitrary code execution. This issue is addressed through improved validation of Sorenson encoded movie files. For Mac OS X v10.6 systems, this issue is addressed in Mac OS X v10.6.5. Credit to an anonymous researcher working with TippingPoint's Zero Day Initiative, and Carsten Eiram of Secunia Research for reporting this issue.