200 Swedish municipalities impacted by a major cyberattack on IT provider
August 28, 2025
Cyberattack on Miljödata disrupted services in over 200 Swedish municipalities, with concerns over stolen sensitive data.
A cyberattack on Miljödata, an IT supplier serving 80% of Swedish municipalities, including Skellefteå, Mönsterås and Kalmar, disrupted services in over 200 municipalities and raised concerns of stolen sensitive data.
The Swedish Privacy Agency confirmed that it has already received around 70 reports of cyber incidents.
The cyberattack occurred over the weekend. The affected systems are used by managers and HR to handle medical certificates, rehabilitation matters, and the reporting and management of work-related injuries.
The company is investigating the incident and has already reported it to the local authorities.
“On Saturday, August 23, it was detected that parts of Miljödata’s IT environment had been subjected to a cyber attack. The attack has been reported to the police.” Miljödata CEO Erik Hallén told media outlet Aftonbladet.
“We are working very intensively with external experts to investigate what happened, what and who was affected, and to restore system functionality.”
The Swedish government and CERT-SE are closely involved in managing the incident, assisting affected parties, coordinating authorities, and supporting an ongoing police investigation.
“The government receives ongoing information about the incident and is in close contact with the relevant authorities. CERT-SE, tasked with supporting Swedish society in managing and preventing IT security incidents, has offered advice and assistance both to the company involved and to affected customers. The national cybersecurity center is coordinating the actions of the authorities concerned. A police investigation is also underway.” Swedish minister for civil defence, Carl-Oskar Bohlin wrote on X.
“The full extent of the incident has not yet been determined, and it is too early to assess the actual consequences. The government takes questions regarding cyberattacks and IT incidents very seriously and understands the concern and uncertainty such attacks can cause.”
At this time, no ransomware group has publicly claimed responsibility for the Miljödata attack.
However, Swedish police revealed that the company has been the victim of an extortion attempt.
“They have taken over Miljödata’s data environment and are demanding 1.5 bitcoins” said Helena Renberg at the police.
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Pierluigi Paganini
(SecurityAffairs – hacking, Swedish municipalities)
