Business continuity and disaster recoveryCyber mishap causes nuclear power plant shutdown
Worries about critical infrastructure vulnerabilities: The move to SCADA systems boosts efficiency at utilities because it allows workers to operate equipment remotely, but experts say it also exposes these once-closed systems to cyber attacks
A nuclear power plant in Georgia was recently forced into an emergency shutdown for forty-eight hours after a software update was installed on a single computer. The Washington Post’s Brian Krebs writes that the incident occurred on 7 March at Unit 2 of the Hatch nuclear power plant near Baxley, Georgia. The trouble started after an engineer from Southern Company, which manages the technology operations for the plant, installed a software update on a computer operating on the plant’s business network. The computer in question was used to monitor chemical and diagnostic data from one of the facility’s primary control systems, and the software update was designed to synchronize data on both systems. According to a report filed with the Nuclear Regulatory Commission (NRC), when the updated computer rebooted, it reset the data on the control system, causing safety systems to errantly interpret the lack of data as a drop in water reservoirs that cool the plant’s radioactive nuclear fuel rods. As a result, automated safety systems at the plant triggered a shutdown. Southern Company spokeswoman Carrie Phillips said the nuclear plant’s emergency systems performed as designed, and that at no time did the malfunction endanger the security or safety of the nuclear facility. Phillips explained that company technicians were aware that there was full two-way communication between certain computers on the plant’s corporate and control networks. But she said the engineer who installed the update was not aware that that the software was designed to synchronize data between machines on both networks, or that a reboot in the business system computer would force a similar reset in the control system machine. “We were investigating cyber vulnerabilities and discovered that the systems were communicating, we just had not implemented corrective action prior to the automatic [shutdown],” Phillips said. She said plant engineers have since physically removed all network connections between the affected servers.
Krebs writes that computer security experts say the Hatch plant incident is the latest reminder of problems that can occur when corporate computer systems at the nation’s most critical networks are connected to sensitive control systems that were never designed with security in mind. Specifically, experts worry that vulnerabilities were introduced into the systems that regulate the electrical grid as power companies transferred control of generation and distribution equipment from internal networks to supervisory control and data acquisition, or SCADA, systems that can be accessed
