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05 Jul 2005

Teenager admits in court to writing Sasser computer worm, Sophos reports

Jan Hruska
Sophos CEO Dr Jan Hruska showing an audience the impact of Jaschan's worms.

On the first day of his trial in Verden, Germany, Sven Jaschan has admitted writing the Sasser worm which infected millions of computers around the world.

Katharina Kruetzfeldt, a spokesperson for the tribunal, said that 19-year-old Jaschan confessed during the closed-doors hearing that he was responsible for unleashing the malicious code that attacked vulnerable Windows computers in 2004.

"Admitting his involvement was a sensible move by Sven Jaschan," said Graham Cluley, senior technology consultant for Sophos. "The court is likely to respond with a lenient sentence on account of his age at the time of the offences, and because he has confessed his guilt. The court will now be interested in hearing evidence as to the impact of Jaschan's malware."

Sven Jaschan released the Sasser worm at the end of April 2004. The malicious code spread quickly via the internet without using email, striking many organisations including the UK coastguard service and Taiwan's national post office. Shortly afterwards Jaschan, apparently concerned about being caught by the authorities, says he emailed his friends saying that he would stop writing worms, and decided to wipe parts of his hard disk and encrypt viral source code on his computer.

But the following month, one of Jaschan's schoolfriends revealed the worm author's identity to Microsoft. The house Jaschan shared with his mother and stepfather was raided by the authorities who issued a search warrant. Computer crime officers searched the house, disconnecting PCs, taking photographs, and collecting CDs and floppy disks.

Despite Jaschan's arrest, his worms have continued to spread across the internet.

Sentencing is expected by the end of the week.

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