TechNet
Vulnerability in Internet Explorer Could Allow Remote Code Execution
Microsoft is investigating new, public reports of a vulnerability in Internet Explorer 6 and Internet Explorer 7. Our investigation has shown that the latest version of the browser, Internet Explorer 8, is not affected. The main impact of the vulnerability is remote code execution. This advisory contains information about which versions of Internet Explorer are vulnerable as well as workarounds and mitigations for this issue.
Our investigation so far has shown that Internet Explorer 8 and Internet Explorer 5.01 Service Pack 4 on Microsoft Windows 2000 Service Pack 4 are not affected, and that Internet Explorer 6 Service Pack 1 on Microsoft Windows 2000 Service Pack 4, and Internet Explorer 6 and Internet Explorer 7 are vulnerable.
http://www.microsoft.com/technet/security/advisory/981374.mspx
