ISPs asked to help clean up Sober worm – Tech News on ZDNet
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Internet service providers were urged on Monday to check their user traffic patterns to locate and shut down machines infected with the mass-mailing Sober worm.

Although Sober is no longer trying to replicate, antivirus company F-Secure believes ISPs must warn infected customers so they can disinfect themselves.

Infected PCs were programmed to download new instructions from the Internet last week, which would have heralded another attack. This update did not actually appear online, but infected machines are still trying to download it.