Iranian Hackers Shut Down British Power Plant for Four Days

Iranian hackers shut down a British power plant for four days in what is believed to be the first successful cyber attack to bring a U.K. generating facility to a standstill.

The affected plant was relatively small, and its closure did not disrupt Britain’s wider electricity supply or generation, according to The Telegraph.

Officials have declined to identify the facility, citing security concerns.

Staff spent four days trying to restore operations after the attack disabled the site.

Unprecedented UK Breach

The incident is believed to be the most successful cyber attack of its kind against British energy infrastructure.

Despite repeated warnings over foreign attempts to penetrate critical national infrastructure, hackers were not previously thought to have succeeded in forcing a U.K. power plant offline.

A government source said the generator was well below the scale at which operators must legally report cyber activity.

“It’s a very small-scale site, less than a rounding error compared to grid capacity,” the source said.

The government added that the wider energy system was never at risk.

Suspected Iran Link

The attack occurred around the same period as a series of cyber breaches affecting water infrastructure across 12 U.S. states.

Those incidents hit wastewater treatment facilities and, in some cases, caused flooding, reduced water pressure, and boil-water advisories.

The FBI attributed the U.S. attacks to “malicious cyber actors”, while government sources later indicated that the threat was likely to have originated in Tehran.

The British attack is not believed to have been intended to cause significant civilian harm and was not widely noticed by the public.

One possible objective was to demonstrate that hackers linked to Iran’s Islamic Revolutionary Guard Corps could penetrate British systems and disable sensitive infrastructure.

Government Response

The U.K. government briefed power company chief executives after the incident and sent businesses advice on security measures and next steps.

The attack was also understood to have been reported to the National Cyber Security Center, the public-facing arm of GCHQ responsible for helping protect national infrastructure from cyber threats.

The NCSC declined to comment on the individual incident.

Its chief executive, Richard Horne, said in June that the agency had dealt with more than 200 attacks on critical national infrastructure over the previous year.

Wider Cyber Threat

British and American intelligence agencies have repeatedly warned about attacks linked to Russia, China, Iran and North Korea.

Previous incidents in Britain have disrupted NHS systems, schools and manufacturing facilities, while other breaches have exposed customer and voter data.

A Cabinet Office risk assessment published last month put the probability of a serious and successful cyber attack against domestic infrastructure at between 5 and 25 percent.

The assessment also warned that artificial intelligence could make cyber operations faster, cheaper and easier to launch.