This indicates an attack attempt to exploit a Buffer Overflow vulnerability in Apple QuickTime.
The vulnerability is due to an error when the vulnerable software handles a maliciously crafted QTVR file containing a malformed QTVRStringAtom atom. A remote attacker may be able to exploit this to execute arbitrary code within the context of the application, via a crafted QTVR file.
Apple QuickTime 7.7.2 and earlier versions for Windows 7, Vista, XP SP2 or later
System Compromise: Remote attackers can gain control of vulnerable systems.
Apply the most recent upgrade or patch from the vendor.