Alert: Critical Windows Attack Underway

A serious new Internet attack affecting Internet Explorer 6 and 7, and Outlook 2002 and later on Windows XP SP2 is underway. If you simply view a Web site or HTML e-mail that's been laced with a poisoned animated cursor file (.ani), an attacker can take over your computer. IE7 under Vista, Firefox and Outlook 2007 are not currently affected.

This is a zero-day attack, meaning there's no patch available as of yet. McAfee and iDefense have reported finding live attacks in the wild, and Andreas Marx of AV Test wrote to tell me there are somewhere around 25,000 Web sites that currently contain this attack or did in the past, according to a Google search for telltale signs within the poisoned sites.