Virus top 10: Sober makes an unwelcome return

After a few months of relative calm from malware writers, two new viruses have broken into the top 10 of malware infections for last month - although they have yet to topple Netsky from the top spot.

Netsky.P retained the number one position, where it has been for two months, vying for the number one position with Zafi.B, first released in June. While Netksy.P is still the most reported virus for the month of November, according to antivirus firm Sophos, with just over 24 per cent of reported infections.

The most reported new virus was Sober.I, which appeared on 19 November and made up around 20 per cent of all infections for the month. Although the Sober virus first surfaced around a year ago, the malware merchants have breathed new life into the virus.

According to Carole Thierault, security consultant at Sophos, said the success of the worm was due to its use of social engineering - by encouraging recipients to open an attachement by claiming it contains important security or messaging information.

The other major virus to hit PCs in November was Bagle.AU, which made up 11 per cent of virus reports.

The list in full

1. Netsky.P 24.2 per cent
2. Sober.I 20.4 per cent
3. Zafi.B 17.9 per cent
4. Bagle.AU 11 per cent
5. Netsky.D 4.4 per cent
6. Netsky.Z 3.9 per cent
7. Bagle.AA 2.6 per cent
8. Netsky.B 2.4 per cent
9. MyDoom.O 2.2 per cent
10. Netsky.Q 2.1 per cent

Others 8.9 per cent