Virus Top 10: Avril Lavigne gets a number one

The Avril worm has topped the virus charts for January - with two versions of the popstar-inspired malware claiming first and second spot and accounting for almost 30 per cent of all virus reports over the month.

Other new entries saw the Yaha variant K go straight in at number five, while newcomer Sobig claimed fourth spot.

The figures released by anti-virus firm Sophos show Klez is still at large - in third place with a 12.1 per cent share of all virus reports.

The Avril worm - also known as Lirva (w32.Lirva@mm) and Naith, once active will attempt to email copies of itself to all contacts on an infected system, shut down all antivirus and firewall programs, and launch a web browser to open the website of Canadian pop starlet Avril Lavigne on an infected user's desktop.

Periodically an infected machine will continue to log-on to the Avril Lavigne website.

The worm shows evidence of a growing trend towards social engineering in the virus world.

In past years emails bearing viruses have increasingly purported to carry information, pictures or video clips of celebrities - often attractive females - in an attempt to encourage users to click on them.

Previous viruses have piggy-backed upon the popularity of singer Jennifer Lopez, tennis ace Anna Kournikova and Latino popstar Shakira.

The full top ten looks like this:

1. W32/Avril-B (Avril variant) 16.8 per cent NEW ENTRY 2. W32/Avril-A (Avril worm) 12.4 per cent NEW ENTRY 3. W32/Klez-H (Klez variant) 12.1 per cent TWELFTH MONTH IN TOP TEN 4. W32/Sobig-A (Sobig worm) 6.1 per cent NEW ENTRY 5. W32/Yaha-K (Yaha variant) 5.7 per cent NEW ENTRY 6. W32/Bugbear-A (Bugbear worm) 5.6 per cent 7. W32/Yaha-E (Yaha variant) 3.3 per cent 8. W32/ElKern-C (Elkern) 2.1 per cent 9. W95/Spaces (Spaces virus) 1.5 per cent 10.W32/Flcss (Funlove) 1.2 per cent