Linux Viruses and Such

'The Slammer worm entered the Davis-Besse plant through a circuitous route. It began by penetrating the unsecured network of an unnamed Davis-Besse contractor, then squirmed through a T1 line bridging that network and Davis-Besse's corporate network. The T1 line, investigators later found, was one of multiple ingresses into Davis-Besse's business network that completely bypassed the plant's firewall, which was programmed to block the port Slammer used to spread.'
'“This is in essence a backdoor from the Internet to the corporate internal network that was not monitored by Corporate personnel,” reads the April NRC filing by FirstEnergy's Dale Wuokko. “[S]ome people in Corporate's Network Services department were aware of this T1 connection and some were not”'