Microsoft: Zombies most prevalent Windows threat | Tech News on ZDNet
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Many Windows PCs have been turned into zombies, but rootkits are not yet widespread, according to a Microsoft security report slated for release Monday.

More than 60 percent of Windows PCs scanned by Microsoft’s Windows Malicious Software Removal Tool between January 2005 and March 2006 were found to run malicious bot software, according to Microsoft. The tool removed at least one version of the remote control software from about 3.5 million PCs, the software maker said.

“Backdoor Trojans…are a significant and tangible threat to Windows users,” Microsoft said in the report.