Code Red gathered steam as the workday spread across the US on Wednesday. Early reports that the worm was going to fizzle out proved to be optimistic as more and more systems became infected as the day progressed.
"This is already one of the largest automatic infections in the history of the internet," said security expert Alan Paller. Chad Dougherty, another expert, said: "It looks like there's a potential for a very large number of machines to be affected."
As Silicon Valley's workday peaked, there was a published report estimating that 150,000 web servers had been hit. The impact of the worm even pushed the Pentagon to shut down a majority of its web sites for the second time in two weeks amid fears that the worm is set to denial of service the White House web servers.
While it was reported that there had been one million downloads of Microsoft's IIS patch, the news was greeted with alarm as there are six million IIS licences around the world.
Further warnings from the FBI's National Infrastructure Protection Centre say that as many as 350,000 more machines could be hit thsi week. More than the worm infected on its initial attack when it first emerged on July 19.
Systems running Windows NT and 2000, as well as the IIS software, can download the patch from Microsoft's website at www.microsoft.com. Companies still using Windows 95, 98 or Me are safe.
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