Last week, a new variant of the MyDoom worm was spreading quickly by e-mail again. The new variant has proved less virulent than previous variants but far more destructive if encountered, according to the anti-virus software firm F-Secure.
The original MyDoom.A worm, discovered in January, infected up to a million computers worldwide in just a few days, clogging the Internet and delaying e-mail. Since then, a number of MyDoom variants have been making the e-mail rounds.
Unlike the previous versions of the virus, MyDoom.F actually goes into an infected computer's hard drive and deletes Windows files like Word documents, Excel spreadsheets, access databases and image files, he said.
According to Reuters, the latest variant arrives in e-mail in-boxes carrying a variety of subject header lines including: "Approved," "Your Credit Card" and "You use illegal File Sharing...Your IP was logged."