Iran-Linked Hackers Force UK Power Plant Offline in Four-Day Attack as GCHQ NCSC Warns of Escalating Nationally Significant Cyberattacks

Iran-linked hackers forced a small UK power generator offline for four consecutive days last month, an incident The Telegraph first disclosed and described as the first successful shutdown of its kind against UK energy infrastructure; the UK government has not formally attributed the intrusion to Iran, with the linkage instead resting on private-sector threat-intelligence assessments 12. The UK government, through the Department for Energy Security and Net Zero, said the facility was "less than a rounding error compared to grid capacity" and confirmed no risk to the wider national grid, noting the site fell below thresholds requiring mandatory incident reporting 12. The National Cyber Security Centre, part of GCHQ, received the incident report but has not identified the facility or commented publicly on specifics 2. NCSC chief executive Richard Horne has said the agency now handles at least four "nationally significant" cyberattacks weekly, after telling reporters in June that the agency had handled more than 200 attacks on critical national infrastructure over the prior year 12. The outage occurred in July around the same time US agencies including the FBI, CISA and EPA warned of Iran-linked actors targeting water utilities across roughly a dozen states, including Minnesota, Michigan, Georgia, South Dakota, New Jersey and Alabama, causing flooding, loss of water pressure and boil-water advisories 12.