Virus Top 10: Make sure you're protected against the latest threats

Klez has maintained the status quo in the virus world by remaining at the top of the latest virus chart - but computer users are being warned about two new entries which have appeared on the list this month.

First up, in at number three, is W32/Gibe-D, a variant of the Gibe virus. It accounted for 4.4 per cent of all virus reports during March.

Gibe's return shows the growing threat to networks posed by employees using peer-to-peer networks. Gibe spread through the popular KaZaA service favoured by music fans and used predominantly for downloading MP3 and other media files.

Graham Cluley, senior technology consultant at Sophos, said: "Indicating the growing popularity of file sharing, this month's highest new entry is Gibe, a worm which spreads via the KaZaA network. Businesses need to have a long hard think about whether these applications have a valid place on their networks."

The second new entry is a newcomer to the charts in any form. The NoClose worm accounted for two per cent of all reports during March, as monitored by Sophos Anti Virus.

However, it is the longevity of Klez - in the top 10 for 14 months now - which continues to amaze industry experts and raise serious concerns about some people's attitude towards security.

"Klez continues to hang around like a bad smell - those hit by it couldn't have updated their anti-virus protection in more than a year," Cluley added.

"Now that it's possible to receive fully automated updates, there's really no excuse. And although it's easy to protect against Klez, it's a seriously nasty virus to recover from."

The full top 10 looks like this:

1. W32/Klez-H (15.3 per cent) 2. W32/Sobig-A (5.2 per cent) 3. W32/Gibe-D (4.4 per cent) 4. W32/Avril-B (3.2 per cent) 5. W32/Yaha-E (3.0 per cent) 6. W32/Avril-A (2.6 per cent) 7. W32/Yaha-K (2.4 per cent) 8. W32/Bugbear-A (2.2 per cent) 9=. JS/NoClose (2.0 per cent) 9=. W32/Lovgate-B (2.0 per cent)

Others 57.7 per cent