“More than four million PCs have been enrolled in a botnet security experts say is almost ‘indestructible,'” BBC News reports.

“The botnet, known as TDL, targets Windows PCs and is difficult to detect and shut down,” The Beeb reports. “Code that hijacks a PC hides in places security software rarely looks and the botnet is controlled using custom-made encryption.”

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“Security researchers said recent botnet shutdowns had made TDL’s controllers harden it against investigation,” The Beeb reports. “The 4.5 million PCs have become victims over the last three months following the appearance of the fourth version of the TDL virus. The changes introduced in TDL-4 made it the ‘most sophisticated threat today,’ wrote Kaspersky Labs security researchers Sergey Golovanov and Igor Soumenkov in a detailed analysis of the virus.”

The Beeb reports, “A botnet is a network of computers that have been infected by a virus that allows a hi-tech criminal to use them remotely. Often botnet controllers steal data from victims’ [WIndows] PCs or use the machines to send out spam or carry out other attacks. The TDL virus spreads via booby-trapped websites and infects a machine by exploiting unpatched vulnerabilities.”

Read more in the full article here.

[Thanks to MacDailyNews Reader “Tony” for the heads up.]

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