"An attacker who successfully exploited this vulnerability could take complete control of the affected system," the Microsoft advisory says. "In a web-based attack scenario, an attacker would host a website that exploits this vulnerability."
However, in what the Redmond, Wash.-based company calls "mitigating factors," for the exploit to work, a user would need to follow a phishing link to reach the malicious website.
Users also are presumably safe if they are running IE 7 because the just-released web browser upgrade turns off the affected ActiveX control by default.
The vulnerability remains unpatched, but Microsoft said it expects to issue a fix in an upcoming security update. The next scheduled patch release is Nov. 14.
As a workaround, the Microsoft advisory suggests users set the kill-bit for the affected ActiveX control. The kill-bit is a feature that prevents ActiveX execution in a user's web browser.
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