Virus firms warn of new email attachment-based malware. A new virus threat called Sober could be causing a few headaches today, according to antivirus researchers. The Sober worm, spotted in the last 12 hours, is a traditional attachment-based piece of malware that uses social engineering to trick people into activating its payload. In contrast with the Flea virus discovered last week, which so far appears to have failed to bite, Sober hides its code in an HTML email. Microsoft Outlook users can activate the payload just by opening the email. Full Story