Kevin Poulson at Security Focus is reporting that a network at Ohio's Davis Besse power plant was brought down earlier this year by the Slammer virus.

According to the article, the intrustion by the virus pulled down its safety monitoring system for five hours, but the owners of the site, First Energy, claim that the downing didn't pose any kind of safety risk. The magazine said the incident came to light after First Energy sent an email to the Nuclear Regulatory Commission (NRC).

The Slammer first penetrated the firewall through an unsecured consultant's network and gained access to the plant through an unsecured T1 line.


Source:

http://www.theinquirer.net/?article=11128