Iran-linked hackers shut down a British power plant for four days in what The Telegraph describes as the most successful cyberattack of its kind against UK energy infrastructure.
“Iran shut down a British power plant for four days in an unprecedented cyber attack, The Telegraph can disclose.” reads the report published by The Telegraph. “It is thought to be the first time that hackers affiliated to the Iranian regime have succeeded in closing down such a facility in the UK, and is believed to be the most successful cyber attack of its kind.”
British officials did not name the power plant because of security concerns. Staff worked for four days to restore it, but the plant was small and the outage did not affect the UK’s wider power supply. Still, the government warned power companies and businesses about the incident and provided guidance on how to respond.
The attack was reported to the National Cyber Security Centre (NCSC), part of GCHQ, which helps protect the UK’s critical infrastructure. The NCSC did not comment on the specific incident.
The US water infrastructure attacks hit dozens of wastewater treatment plants across 12 states, causing flooding and loss of pressure from taps. Authorities in affected areas told customers to boil water. The first reports came from Minnesota on July 26, followed by similar breaches in Michigan, Georgia, South Dakota, and New Jersey. The FBI attributed those incidents to “malicious cyber actors”; US government sources later confirmed the threat most likely originated in Tehran.
The UK attack is not thought to have been designed to harm civilians. The more probable intent was to demonstrate that hackers linked to Iran’s Islamic Revolutionary Guard Corps could gain access to UK infrastructure and shut it down at will. A four-day outage at a small generator that nobody outside the industry noticed is, from that perspective, a successful proof of concept.
Iran has accelerated its cyberattacks on Western countries since the US and Israel began air strikes in February. Suspected Iranian operations have been reported in Germany, Poland, Finland, Belgium, and Albania, with Israel and other Middle Eastern countries remaining the most frequent targets. In March, the NCSC advised British organisations to review their security posture in light of the wider conflict. NCSC chief executive Richard Horne said in June that the agency had handled more than 200 attacks on critical national infrastructure in the previous year alone.
The timing is awkward for the intelligence and security committee, which oversees UK spying agencies.
“Experts have long warned that the UK is unprepared for the scale of the threat of malicious cyber attacks from foreign adversaries, and the intelligence and security committee, which oversees spying agencies, reported last year that the chance of an Iranian cyber attack on British infrastructure was “unlikely”.” continues the report.
A Cabinet Office risk assessment published last month placed the probability of a serious and successful cyberattack on domestic infrastructure at between five and twenty-five percent. The same document warned that AI is making attacks faster and cheaper to run, and is lowering the technical bar for anyone wanting to attempt them.
The government’s public response leaned hard on the size of the target. A government source told The Telegraph: “We have thresholds for important generators to legally notify us of cyber activity, and this site is nowhere near. It’s a very small-scale site, less than a rounding error compared to grid capacity.”
A government spokesman said the UK has a strong and resilient energy system and that the incident never threatened the wider power network. While both statements are technically true, they do not answer a key question: should it be considered acceptable for even a small power plant to remain offline for four days?
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(SecurityAffairs – hacking, Iran-Linked Hackers)