Sophos: Top 10 Viruses and Hoaxes in January 2003

This is the latest in a series of monthly charts counting down the ten most frequently occurring viruses and hoaxes as compiled by Sophos, a world leader in corporate anti-virus protection.

For January 2003, the virus chart is as follows, with the most frequently occurring virus at number one:

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


The Avril worms, first seen in the wild at the beginning of January, account for almost 30% of support queries. They have taken the top two spots of this month’s virus top ten. Other new entries to make the top ten were the Yaha-K and Sobig worms.

“2002 ended with a few persistent offenders dominating the virus chart,” said Graham Cluley, senior technology consultant, Sophos Anti-Virus. “2003 kicked off with another kind of offender – virus writer Simon Vallor, who has been sentenced to jail for two years.”

“This month also saw the arrival of the Slammer worm – exploiting a six month old vulnerability. It reinforced the need for everyone to ensure their patches are kept up to date,” continued Cluley.

Sophos detected 521 new viruses, worms and Trojan horses in January. The total number it now protects against is 79,538.

The top ten hoaxes reported to Sophos during January 2003 are as follows:

2. WTC Survivor 12.2%
3. Budweiser frogs screensaver 8.1%
4. Meninas da Playboy 7.8%
5. Bonsai kitten 5.8%
6. Hotmail hoax 4.5%
7. Applebees Gift Certificate 3.7%
8. A virtual card for you 3.0%
9. Bill Gates fortune 2.5%
10. Elf Bowling 2.1%

Others 30.5%

“The JDBGMGR hoax is still the most problematic of the email hoaxes,” continued Cluley. “We all have a part to play in slowing down the spread of this hoax. If you receive this email, simply delete it.”

Sophos has made available a free, constantly updated information feed for intranets and websites which means users can always find out about the latest viruses and hoaxes:

Graphics of the above Top Ten virus chart are available at

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