Data Spike Connected to Nuclear Power Plant Shutdown

Via SecurityFocus -

The U.S. House of Representative's Committee on Homeland Security called this week for the Nuclear Regulatory Commission (NRC) to further investigate the cause of excessive network traffic that shut down an Alabama nuclear plant.

“ If you were to test any control systems that have any more than three or four different network-connected devices, they could be knocked over very easily. ”

Dale Peterson, CEO, DigitalBond During the incident, which happened last August at Unit 3 of the Browns Ferry nuclear power plant, operators manually shut down the reactor after two water recirculation pumps failed. The recirculation pumps control the flow of water through the reactor, and thus the power output of boiling-water reactors (BWRs) like Browns Ferry Unit 3. An investigation into the failure found that the controllers for the pumps locked up following a spike in data traffic -- referred to as a "data storm" in the NRC notice -- on the power plant's internal control system network. The deluge of data was apparently caused by a separate malfunctioning control device, known as a programmable logic controller (PLC).

In a letter dated May 14 but released to the public on Friday, the Committee on Homeland Security and the Subcommittee on Emerging Threats, Cybersecurity, and Science and Technology asked the chairman of the U.S. Nuclear Regulatory Commission to continue to investigate the incident.

"Conversations between the Homeland Security Committee staff and the NRC representatives suggest that it is possible that this incident could have come from outside the plant," Committee Chairman Bennie G. Thompson (D-Miss.) and Subcommittee Chairman James R. Langevin (D-RI) stated in the letter. "Unless and until the cause of the excessive network load can be explained, there is no way for either the licensee (power company) or the NRC to know that this was not an external distributed denial-of-service attack."