Microsoft has put a price of $250,000 on the head of the creator of the Conficker internet worm, as reported in our blog yesterday.

Conficker, which is spreading through unprotected PCs via the internet and external storage devices, is the latest piece of “malware” to hit PCs running the Microsoft Windows software.

“Writing malicious software like this is a criminal act,” Cliff Evans, the security and privacy head for Microsoft, told The Times. “We want to bring the perpetrators to justice.”

Microsoft issued system patches to protect against Conficker last year and hopes that the publicity generated by the reward money will encourage its customers to apply the patches. Complete information about Conficker is available on the Microsoft website.

This is not the first time that Microsoft has offered a reward for the capture of internet criminals. In 2003 the company put up $500,000 (£345,000) for the conviction of the author of the Blaster and Sobig worms and in May 2004 Microsoft paid $250,000 to a group of German students whose classmate, Sven Jaschan, was the author of the Sasser and Netsky worms. Jaschan was given nine months’ probation.

One peculiar aspect of the current case is that no one seems to know exactly what the Conficker worm is for. Graham Cluley, of the security specialist Sophos, told The Times: “It’s as if someone is assembling an army of computers around the world, but hasn’t yet decided where to point them.”

His hope, he said, is that “the publicity generated by the reward will scare them [the perpetrators] off, and it will never be activated. If it were activated, for spam e-mails say, it would be fairly easy to track down the source and secure a conviction.”

Mr Cluley added: “If they are not scared off, then I’m not sure that $250,000 is enough to secure any information. We need to remember that the people behind this sort of attack are now highly organised criminals. We are not dealing with spotty teenagers any more.”

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