This indicates an attack attempt to exploit a Use-After-Free vulnerability in Apple QuickTime's ActiveX control.
The vulnerability, which is located in the "QTPlugin.ocx" ActiveX control, can be exploited through misuse of the vulnerable method Clear(). An attacker can exploit this by tricking an unsuspecting user into visiting a malicious webpage and execute arbitrary code within the context of the application.
Apple Quicktime prior to 7.7.3
System Compromise: Remote attackers can gain control of vulnerable systems.
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