This indicates an attack attempt to exploit a Memory Corruption vulnerability in Apple QuickTime.
The vulnerability is due to insufficient validation when parsing a 3gp file with a malformed atom. A remote attacker may be able to exploit this to execute arbitrary code within the context of the application, via a crafted QuickTime 3gp file.
Apple Quicktime 7.7.6 in Windows 7 and Windows Vista
Apple Quicktime 7.7.7 in Windows 7 and Windows Vista
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.