US security house website knocked out

US officials at the federally funded security clearing house the Computer Emergency Response Team (Cert) have confirmed that it has been hit by a Denial of Service (DoS) attack.

In such an attack, malicious users deploy special tools that create a flood of data which renders a site unreachable by users.

"We are working with our service providers to resolve this problem," Bill Pollack, public relations co-ordinator for the Cert.org site, said in a statement.

Based at Carnegie Mellon University, Cert co-ordinates the communications among the response teams throughout US government agencies, universities and companies. It is a major reporting centre for internet security problems, and analyses product vulnerabilities. It also publishes technical documents.

Cert, which acknowledged that DoS attacks are common, was hit by a similar attack in May. Richard Pethia, director of the Networked Systems Survivability Program at Carnegie Mellon's Software Engineering Institute, which includes Cert, said at the time that it was "just another attack".

"The lesson to be learned here is that no one is immune to these kinds of attacks," he added. "They cause operational problems and it takes time to deal with them."