This indicates an attack attempt against a denial of service vulnerability in Microsoft Internet Explorer.
The vulnerability is due to MSIE failing to handle large values in the "StartColorStr" and "EndColorStr" properties of the ActiveX object, resulting in a stack overflow. It allows remote attackers to cause a denial of service by sending a crafted html page.
Microsoft Internet Explorer 6.0 SP2
Denial of Service: Remote attackers can crash vulnerable systems.
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