MyDoom worm brought down US software maker SCO group's website forcing the company to set up a new domain name. But the worm is on the wane, said analysts.

They said the worm had infected over one million computers worldwide and highlighted the vulnerability of the Internet to infections that allow affected computers to be controlled for hacker attacks.

"The question that must be asked at this stage is how easy would it be for a potential extremist to hold our computer dependent society to ransom using Mydoom type sophisticated threats," Internet security firm mi2g said in a statement.

"The more we study MyDoom the more clear it becomes that the perpetrator is a clever strategist combined with being a sophisticated programmer," said D K Matai, executive chairman of mi2g. "Especially because SCO had five days advance notice to prepare."

SCO, which owns Unix operating system for large server computers, was shut down

Sunday though a so-called denial-of-service attack, with infected computers bombarding its www.sco.com site with information requests over 60 times a minute.

SCO said on Monday it was setting up a new domain www.thescogroup.com as the company's website through February 12.

Agencies