Virus Top 10: Sober return topples Zafi

The return of Sober (variant N) has seen it rocket to the top of the current threat list, heading the chart of most prolific viruses during the past month.

IT managers in their daily firefight against viruses saw a massive spike in the instances of Sober-N as it displaced Zafi-D atop the 'least wanted' list provided by antivirus firm Sophos.

In total Sober-N accounted for 43.8 per cent of all reported viruses. So if you have noticed a large number of emails in your inbox with German text, some seeming to offer tickets for the Fifa World Cup 2006, this will be why. That message text, as well as subject lines referring to passwords or a booking confirmation were typical of the spread of this email worm.

Carole Theriault, security consultant at Sophos, said: "Sober-N stormed to the top of the chart in early May, making it one of the biggest outbreaks so far this year. This manipulative email worm spread quickly, using social engineering tricks, such as offering free World Cup tickets, to entice recipients into opening the infected attachment."

Recent arrival on the virus landscape Mytob (Z and AZ variants) also made its presence felt.

The full top ten looks like this:

1 Sober-N 43.8 per cent (New entry)
2 Zafi-D 14.5 per cent
3 Netsky-P 13.1 per cent
4 Netsky-D 3.1 per cent
5 Zafi-B 2.0 per cent
6 Mytob-AZ 1.6 per cent (New entry)
7 Mytob-Z 1.5 per cent
=7 Netsky-Z 1.5 per cent
=7 Mytob-E 1.5 per cent
10 Netsky-N 1.4 per cent

Others: 16.0 per cent