A new e-mail-borne worm discovered Monday targets Microsoft Windows and sends messages to addresses found in the Windows Address Book.
The worm arrives by mail with the subject line “Re: your password!” and exploits vulnerabilities to execute when the recipient reads or previews the file. The worm sleeps for several hours, and then copies itself to a Windows directory so it can be executed each time Windows is started.
The worm is called W32.Frethem.K@mm. It uses its own Simple Mail Transfer Protocol engine to send itself to e-mail addresses that it finds in the Microsoft Windows Address Book and in .dbx, .wab, .mbx, .eml, and .mdb files. It doesn't affect Unix, Macintosh, or Linux systems.
Source: www.techweb.com