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08 May 2006

Two years after author's arrest, Netsky worm still tops virus chart

Author of Sasser and Netsky worm arrested 24 months ago, but malware still spreads

Sven Jaschan
Sven Jaschan ultimately walked free from the court

Two years ago today, on 8 May 2004, a German teenager was arrested in connection with the widespread Sasser and Netsky worm outbreaks.

18-year-old Sven Jaschan of Waffensen, North Germany, wrote a series of worms which hit tens of millions of computers around the world. Experts at SophosLabs™, Sophos's global network of virus, spyware and spam analysis centers, have revealed that some of the worms created by Jaschan worms continue to have a major impact 24 months later.

Jaschan's Netsky-P worm was found to have been responsible for 18.5% of all viruses reported at email gateways in April 2006.

"Two years have passed but Sven Jaschan's Netsky-P worm is still the number one reported virus in the world, despite him having been arrested and found guilty in the meantime," said Graham Cluley, senior technology consultant for Sophos. "Every anti-virus program - even the crummiest ones - can detect the Netsky worm, and have been able to for years. This tells us that there are still many people out there who aren't using any anti-virus software at all, but are busy passing on an old pox to others."

Sven Jaschan ultimately walked free from a German court, being punished with 30 hours community service. A poll of 550 business users conducted by Sophos found that 78% believed his sentence was not harsh enough.

"It's like the classic story of Pandora's Box. Viruses and worms, once released can never be put back - regardless of whether their creator is punished or regrets his or her actions," continued Cluley. "The malware that Jaschan released on mankind is likely to continue spreading for years to come."

Sophos continues to recommend that companies protect their email with a consolidated solution to thwart the virus, spyware and spam threats as well as secure their desktop and servers with automatically updated anti-virus protection. Sophos also recommends that users are educated in safe computing guidelines to help reduce the risks.

About Sophos

More than 100 million users in 150 countries rely on Sophos as the best protection against complex threats and data loss. Sophos is committed to providing complete security solutions that are simple to deploy, manage, and use and that deliver the industry's lowest total cost of ownership. Sophos offers award-winning encryption, endpoint security, web, email, mobile and network security solutions backed by SophosLabs - a global network of threat intelligence centers.

Sophos is headquartered in Boston, US and Oxford, UK. More information is available at