Feeds

'Data storm' blamed for nuclear plant shutdown

Malfunctioning control device causes fatal spike in traffic

5 things you didn’t know about cloud backup

No digital contagion has been fingered in the latest incident, said Terry Johnson, spokesman for the Tennessee Valley Authority, the public power company that runs the Browns Ferry power plant.

"The integrated control system (ICS) network is not connected to the network outside the plant, but it is connected to a very large number of controllers and devices in the plant," Johnson said. "You can end up with a lot of information, and it appears to be more than it could handle."

The device responsible for flooding the network with data appears to be a programmable logic controller (PLC) connected to the plant's Ethernet network, according to an NRC information notice on the incident (PDF). The PLC controlled Unit 3's condensate demineralizer - essentially a water softener for nuclear plants. The flood of data spewed out by the malfunctioning controller caused the variable frequency drive (VFD) controllers for the recirculation pumps to hang.

Such failures are common among PLC and supervisory control and data acquisition (SCADA) systems, because the manufacturers do not test the devices' handling of bad data, said Dale Peterson, CEO of industrial system security firm DigitalBond.

"What is happening in this marketplace is that vendors will build their own (network) stacks to make it cheaper," Peterson said. "And it works, but when (the device) gets anything that it didn't expect, it will gag."

In many cases, a simple vulnerability scan will even cause the devices to crash, Peterson said. During tests in an electrical substation, Nessus running in safe scan mode crashed devices, he said. In some cases, sending out broadcast data on the network will crash several of connected devices, he added.

"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," Peterson said.

The Browns Ferry nuclear power plant has had its share of difficulties. All three units of the plant were shutdown in 1985 due to performance and management problems, according to the NRC. Unit 2 was restarted in 1991, and Unit 3 started operating again in 1995. On Tuesday, the NRC gave the Tennessee Valley Authority permission to restart Unit 1.

The Committee on Homeland Security gave the NRC until 14 June to respond to its letter.

This article originally appeared in Security Focus.

Copyright © 2007, SecurityFocus

The essential guide to IT transformation

More from The Register

next story
One HUNDRED FAMOUS LADIES exposed NUDE online
Celebrity women victimised as Apple iCloud accounts reportedly popped
Rubbish WPS config sees WiFi router keys popped in seconds
Another day, another way in to your home router
Goog says patch⁵⁰ your Chrome
64-bit browser loads cat vids FIFTEEN PERCENT faster!
NZ Justice Minister scalped as hacker leaks emails
Grab your popcorn: Subterfuge and slur disrupts election run up
HP: NORKS' cyber spying efforts actually a credible cyberthreat
'Sophisticated' spies, DIY tech and a TROLL ARMY – report
NIST to sysadmins: clean up your SSH mess
Too many keys, too badly managed
Scratched PC-dispatch patch patched, hatched in batch rematch
Windows security update fixed after triggering blue screens (and screams) of death
Attack flogged through shiny-clicky social media buttons
66,000 users popped by malicious Flash fudging add-on
New Snowden leak: How NSA shared 850-billion-plus metadata records
'Federated search' spaffed info all over Five Eyes chums
prev story

Whitepapers

Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Endpoint data privacy in the cloud is easier than you think
Innovations in encryption and storage resolve issues of data privacy and key requirements for companies to look for in a solution.
Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
Consolidation: The Foundation for IT Business Transformation
In this whitepaper learn how effective consolidation of IT and business resources can enable multiple, meaningful business benefits.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?