Conficker Worm Infects 3.5M Windows PCs So Far

F-Secure, a security firm based in Finland, conservatively estimates that 3.5 million Windows PCs have been infected with a new worm called “Downadup” or “Conficker.” It is infecting Windows computers at a rate of more than 1 million in the past 24 hours. According to ComputerWorld, the worm exploits “a bug in the Windows Server service” that is used in all versions of Windows currently supported by Microsoft; including Windows 2000, Windows XP, Windows Vista, Windows Server 2003 and Windows Server 2008.

Microsoft recommends that Windows users install an update provided in late October and follow that up by running the latest version of their Malicious Software Removal Tool (MSRT) which was updated this January in response to the Downadup worm. There is another cure, however.

Update: According to Panda Security, the Downadup outbreak is now an epidemic. Additionally, F-Secure notes that “Downadup disables Automatic Updates, so updated versions of MSRT will need to be downloaded manually, it will not be automatically installed on infected machines.”