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Windows on the Web
-- by James E. Powell
Virus squasher McAfee has discovered the first macro computer virus to target Microsoft Mail users. The so-called ShareFun virus searches an e-mail directory and automatically generates and transmits e-mail messages with virus-infected attachments.
ShareFun affects Microsoft Word versions 6.0 and 7.0. The virus invades a system when an infected Word document is opened, then runs a self-contained random number generator that results in a 25 percent probability of the virus taking a second action. During this second action, the virus searches the hard drive for Mail, then accesses the e-mail directory and chooses three random addresses. ShareFun then generates an e-mail message for each addressee and attaches an infected Word document. ShareFun also infects all subsequent Word documents opened from within Word.
"The virus is especially pernicious because it tricks recipients into believing they were sent the file by a trusted friend," says Jimmy Kuo, the director of McAfee's Anti-Virus Emergency Response Team.
McAfee discovered the virus when a customer submitted a suspicious sample. The company posted a detector for the virus on its Web site and developed a special update of its VirusScan software with an antidote. You can download the free working evaluation version from McAfee's Web site at http://beta.mcafee.com/public/dosscan/betascan.zip. McAfee has also shared the virus sample with other antivirus researchers.