Top ten viruses and hoaxes reported to Sophos in July 2004

Sophos Press Release

Largest number of new viruses recorded since December 2001 - Zafi worm still spreading at staggering rate

Sophos, a world leader in protecting businesses against spam and viruses, has published a report revealing the top ten viruses and hoaxes causing problems for businesses around the world.

The report shows that the Hungarian Zafi worm continues to dominate the virus chart, accounting for more than half of all viruses spotted by Sophos's global network of monitoring stations. The number of new viruses being written is on the increase too, with Sophos identifying a total of 1,157 brand new viruses during the month - the highest figure since December 2001.

The top ten viruses in July 2004 were as follows:

Position Last
Malware Percentage of reports

"The Zafi worm, which can arrive in several different languages, won't be disappearing anytime soon. There are so many copies of Zafi-B flying around and trying to break through companies' defences," said Carole Theriault, security consultant at Sophos. "It is vital that computer users around the world are protected fully to ensure worms like these don't hang around like a bad smell."

"MyDoom-O, first seen on 26 July, has also been spreading successfully, needing only a few days to burst into the Sophos chart of top ten viruses. It used an unprecedented technique of infecting computers, scooping up email addresses and polling search engines for more addresses to bombard. MyDoom-O hit Google particularly hard, and millions of users were unable to access the search engine," continued Theriault.

Sophos analysed and protected against 1,157 new viruses in July. The total number of viruses Sophos now protects against is 92,645. Sophos figures show that over 9% of emails circulating during the month of July were viral.

"This is the first time since December 2001 that Sophos has issued protection for so many threats. Unfortunately, it looks like the number of new viruses we see each month is growing rather than shrinking. When compared to the same period last year, we have issued protection for 532 more viruses this month," said Theriault.

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

"The Hotmail hoax returns to the top spot this month as we continue to see the same hoaxes causing problems month after month," continued Theriault. "Administrators are advised to set up a company policy telling all users not to forward hoaxes to friends or colleagues."

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 virus Top Ten chart are available here.

More information about safe computing, including anti-hoax policies.

Position Hoax Percentage of reports
1Hotmail hoax
2Meninas da Playboy
3Bonsai kitten
4WTC Survivor
5A virtual card for you
6Budweiser frogs screensaver
8Bill Gates fortune
10Jamie Bulger

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