This fast-moving, mass-mailing invader became the top worm in North America almost overnight.
A powerful worm known variously as w32/Novarg.A, w32/Shimg, w32/Mydoom, or w32/Mimail.R began devastating personal and corporate e-mail systems across the globe in late January. This fast-moving, mass-mailer Internet worm apparently started spreading on the popular peer-to-peer file-sharing application Kazaa and then moved to e-mail. The virus overwrites certain system files, e-mails itself to every e-mail address it finds on a victims machine, and opens a back door to malicious attacks. It affects systems running Windows 95 or later. It became the top worm in North America almost overnight, and most antivirus companies had elevated the threat level to high or dangerous.
To find out how to protect your system from MyDoom, see our full article