The Netsky worm beat off a strong challenge from various Bagle virus variants to top the malware charts last month.

Message filtering firm MessageLabs blocked more than four million Netsky-infected emails in March. Netsky-C (2 million plus interceptions over the last four weeks) and Netsky-B (1.2 million). The other entrants in MessageLabs' Top 10 were insignificant by comparison. Bagle-J was the worst of the numerous Bagle variants released by VXers this month in a tit-for-tat conflict with the unknown authors of Netsky.

Records of support calls logged by antivirus firm Sophos tell a similar picture. Almost three in five support calls logged by Sophos in March involved the Netsky worm. Netsky-D, alone, accounted for more than 30 per cent of support calls to Sophos.

"The authors of the Netsky and Bagle worms have been battling for virus writing supremacy in March, with both releasing new variants in a tit-for-tat game of one-upmanship," said Carole Theriault, a security consultant at Sophos. "The Netsky author wins the dubious accolade of the month's biggest virus, accounting for almost 60 per cent of all reports to Sophos, but the biggest losers are the innocent computer users who have been caught in the crossfire of the Netsky/Bagle spat."

Sophos added protection against 824 new viruses in March, bringing the total number of viruses it protects against to 89,112. ®

March 2004 Virus Chart, by Sophos

1. Netsky-D
   
2. Netsky-B
   
3. Netsky-C
   
4. Bagle-C
   
5. Netsky-J
   
6. Bagle-E
   
7. Netsky-P
   
8. Bagle-H
   
9. Bagle-J
   
10. MyDoom-A

Related stories

War of the worms turns into war of words
Netsky-D makes your PC go beep, beep, beep
MyDoom and Netsky cause chaos
Netsky author signs off
Latest Bagle worms spread on auto-pilot