Security companies have raised the alert for the new Sober worm variant reportedly making its rounds in e-mail messages in English and German.
F-Secure has rated it a Radar Level 1 Alert, which is the highest alert on its three-step rating system. The Finland-based company said on its Web site that "several millions of infected e-mails have been seen by Internet operators over the last hours".
Symantec rated it a level 3 threat, with level 5 being the most severe. In a media statement Wednesday, the company said it has detected more than 1,600 potential threats from among its corporate customers, and over 300 from consumers, since Nov. 19. Twenty-three of these were identified by sensors located in the Asia-Pacific region.
McAfee's Anti-virus and Vulnerability Emergency Response Team (AVERT) up its alert on the worm to medium on Wednesday, and also reported that it detected over 300 reports of the virus from unique senders. Trend Micro, similarly, has issued a medium alert in an earlier report.
The worm is propagated via e-mail attachments purported to be questions from law enforcement agencies or video clips and pictures. Once an attachment is opened, it automatically replicates and sends the e-mail to addresses found in the user's compromised machine.