Sophos, computer security firm in London have warned users about a new variant of the Sober worm purporting to be an email from the soccer world governing body FIFA offering free tickets to the 2006 World Cup in Germany.
In the last 24 hours the W32.Sober-N worm raced to the top of the most widespread virus chart, accounting for 62% of all viruses seen by Sophos monitoring stations around the world. This worm like other Sober worms, uses a subject header in an e-mail to try to entice people into opening an attachment. When a user opens the attached file they will become infected by the worm, and it will mass-mail itself to other email addresses found on the infected PC.
The variant has been compressed to make it difficult for anti-virus software to identify when scanning a system.