stieglmant writes "For everyone who thought the 'blackout of 2003' was bad, how about this, according to an article at SecurityFocus, and another article at The Register, 'The Slammer worm penetrated a private computer network at Ohio's Davis-Besse nuclear power plant in January and disabled a safety monitoring system for nearly five hours.'" Russell writes "Maryland MARC Train Service was shut down most of Wednesday morning due to what sounds like the MS-Blast worm or one of its variants. The local Baltimore news reports that the cause was a signal malfunction but CSX, whose communications system runs the tracks, has an article describing the shutdown as a result of 'a worm virus similar to those that have infected the systems of other major companies and agencies in recent days'. This indicates that the network that the train signaling stations are on is not protected by firewalls, at least to block ports 135 and 444 where the DCOM vulnerability is attacked. Wow, taken to the extreme, the exploitation of their systems could have caused a train collision and injury or death to hundreds of Maryland and Virginia commuters."