A period of comparative virus-free peace may be over with news of a potentially destructive new worm.
Trend Micro has warned that 'Winevar' targets Windows systems and has the potential to delete files.
The worm propagates using its own Simple Mail Transfer Protocol engine and sends emails to addresses it gathers from infected systems.
It uses a known exploit in Windows that automatically executes its attachment without a click on the part of the recipient, and can also prevent antivirus protection from working.
Trend Micro said that the email arrives with 'N 4' in the subject line and carries two attachments - one a GIF, the other a TXT file - with random number values.
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