Nimda hits broadband users

Users of BT's ADSL broadband service suffered severe connectivity problems on Wednesday when equipment at two exchanges was hit by what the company believes was the Nimda worm.

A recorded message on the company's helpline told callers that it was experiencing problems, with users having trouble connecting to the Internet. The message said this could be "due to the recent outbreak of the Nimda virus." Both the Whitefield and the London Lodge Hill exchanges were affected.

The Nimda virus first surfaced on Tuesday, and has been blamed for causing disruption to the Internet.

The Nimda worm uses several methods to propagate itself, including email attachments and IRC, but it's most worrying property is a Code Red-like ability to exploit known weaknesses in Microsoft's IIS Web server software.The Nimda virus -- its full name is W32/Nimda.A-mm -- was first detected on Tuesday afternoon. Messagelabs, which provides an email scanning service for its corporate customers, said it stopped more than 100 copies of the virus attached to emails within an hour of the first incident, which arrived from Korea at 13.10GMT. Most of the Nimda email viruses captured on Tuesday afternoon by Messagelabs originated from the US, leading the company to speculate that this is where the virus originates from.

BT was not available for comment at the time of going to press.

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