Multiple London councils, including Chelsea and Westminster, faced a cyberattack that may have exposed resident data. Authorities are actively investigating the incident.
A cyberattack struck multiple London councils, including Kensington & Chelsea and Westminster, which share IT systems. Officials say residents’ data may have been compromised and have notified the UK Information Commissioner’s Office. The councils are working to secure systems but say it is too early to identify who is behind the attack.
Royal Borough of Kensington and Chelsea (RBKC) announced that the council is investigating the cybersecurity incident with the help of National Cyber Security Centre (NCSC) and external cybersecurity experts.
Sky News, citing Graeme Stewart, head of public sector at Check Point, reports that the situation shows “all the signs of a serious intrusion.” Stewart highlighted that the attack caused multiple boroughs to go offline, exposed shared infrastructure, and likely enabled lateral movement after credential compromise, indicating a severe breach of the target.
Councils’ rapid shutdown reflects the high-risk nature of the incident, with potential for sensitive data theft or encryption.
RBKC council has yet to link the attack to a specific threat actor.
“At this stage it is too early to say who did this, and why, but we are investigating to see if any data has been compromised – which is standard practice.” an RBKC spokesman told Sky News. “Our IT teams worked through the night yesterday and a number of successful mitigations were put in place, and we remain vigilant should there be any further incidents or issues.”
Councils manage highly sensitive citizen data, including social care records, identity documents, housing information and financial details. If cybercriminals gained access to these systems, they could enable precise identity theft, large-scale fraud and ruthless extortion.
The impact would extend beyond a single town or region because compromised data often involves people who move, work, or have connections nationwide. Attackers could reuse stolen information across multiple sectors, institutions, and services, creating cascading harm and undermining trust in public authorities.
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Pierluigi Paganini
(SecurityAffairs – hacking, London councils)
