AMSTERDAM: Spotty teenage hackers who set off global email viruses are being replaced by serious online crooks whose stealth attacks don’t make headlines but cause more damage, security software makers said on Tuesday.

“Two years ago we stayed up all night, concerned about a great mass-mailing worm,” said Mario Juarez, a product manager at the security business unit of US-based Microsoft.

“Today, we worry not about a virus that will take every machine down, but that may attack one machine or a set of machines,” he said in an interview at a Microsoft Tech Ed developers conference.

“What you see more of are a variety of attacks that are carried out to make money, such as stealing credit card details or threatening a website with a denial of service attack unless it pays then money.”

He spoke on the same day a 19-year old German man admitted in court he had written the Sasser computer worm.

In 2004 the worm knocked out an estimated one million computer systems among home users and companies by spreading on the ubiquitous Microsoft Windows operating system.

The US computer giant has since had to close many open back doors in its software and fix other security holes. After issuing a series of patches, it claims its software is a lot safer now. More improvements are planned.

“Today in Outlook Express, if you click on a link, the virus programme won’t execute,” said Detlef Eckert, senior director for trustworthy computing at Microsoft’s European organisation, referring to Microsoft’s email software.

What helps is that consumers are better informed about viruses and worms and have become reluctant to open email attachments that may unleash a harmful computer programme.

But the targeted robberies of individuals or small groups of people are more sophisticated than the mass-mailing worms that created only modest damage.

Some new viruses now infect websites and can then enter personal computers that are well protected, Eckert said.

“Very often, these customers don’t know they are at risk, or even that they are being attacked,” he said..—Reuters