GFI Software researchers warn that searches on Bing for Adobe Flash can bring up an ad claiming to link to a Flash 10 download site.

"Of course, what those users get isn't Flash, but a kick in the digital teeth in the form of the ZeroAccess Trojan," writes Threatpost's Dennis Fisher. "This piece of malware, also known as Max++ and Sirefef, is a particularly ugly pest and includes some rootkit functionality that gives it the ability to stay resident on an infected machine even after cleanup attempts and reboots."

"ZeroAccess also is being used in an ongoing attack discovered last week by researchers at Dell SecureWorks in which users are redirected from compromised sites to an attack site that installs the Trojan," Fisher writes.

Go to "Malicious Ads on Bing Lead to ZeroAccess Trojan" to read the details.

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