This indicates an attack attempt against a buffer overflow vulnerability in Apple Safari WebKit.
This issue is caused by an error in the DOM level 2 implementation in WebKit when handling a range object. It may allow remote attackers to execute arbitrary code by sending a crafted web page.
Apple iTunes before 10.2 on Windows and Apple Safari
System Compromise: Remote attackers can gain control of vulnerable systems.
Refer to the vendor web site for suggested workaround.