The pro-Russian hacker group Server Killers has claimed responsibility for the biggest cyberattack ever recorded against Norwegian government digital services, targeting the Norwegian Digitalization Agency (Digdir) in what it called a declaration of cyber war following Oslo’s latest Ukraine aid commitment.
The Server Killers Norway cyberattack began on Monday and was ongoing as of Wednesday, Digdir spokesman Are Kvistad told the Associated Press.
‘It’s the biggest attack against Digdir solutions that we have ever experienced,’ Kvistad said.
Services held up despite Server Killers Norway cyberattack
The assault was a denial-of-service attack, pushing massive volumes of traffic at the agency to knock services offline. Among those targeted was a platform allowing Norwegian citizens to log in across multiple public services with a single set of credentials.
Kvistad said Digdir managed to keep its services running ‘practically all the time’ despite the pressure.
Server Killers announced responsibility in a Telegram post on Wednesday, widely reported by Norwegian media. The group said it had declared cyber war on Norway after the country renewed its security cooperation with Ukraine on 23 August.
On Sunday, Norwegian Prime Minister Jonas Gahr Støre announced during a visit to Kyiv that Norway would provide 85 billion Norwegian crowns ($9.2 billion) to Ukraine from next year’s state budget, for a third year in a row. The two countries also agreed further cooperation on drone technology and other forms of modern warfare.
Norwegian officials had not commented on the hackers’ claim by publication time.
Group active since 2023 with attacks across Europe and beyond
According to Ukrainska Pravda, Server Killers describe themselves as a pro-Russian hacker group that has been active since 2023. Earlier in August, the group claimed responsibility for similar cyberattacks on Romanian and Canadian websites.
Norwegian media have reported that Server Killers were linked directly or indirectly to previous cyberattacks in Norway and other European countries.
The attack fits a broader pattern across the continent. All European countries are on high alert as Russia has stepped up sabotage and malign activity since its full-scale invasion of Ukraine in February 2022. Officials say the attacks are designed to undermine support for Ukraine, spread fear and discord in European societies, and drain investigative resources.
In 2025, Norwegian authorities said Russian hackers were likely behind suspected sabotage at a dam in the country. Hackers gained access to a digital system that remotely controls one of the dam’s valves and opened it to increase water flow. A three-minute video showing the dam’s control panel and a mark identifying a pro-Russian cybercriminal group was published on Telegram at the time, police said.
Danish authorities have also blamed Russia for cyberattacks against infrastructure and websites in Denmark in 2024 and 2025. Officials said pro-Russian group Z-Pentest carried out a ‘destructive attack’ on a water utility company in 2024, while a separate group, NoName057(16), was responsible for an attack on Danish websites ahead of the 2025 local elections. Both groups have links to the Russian state, officials said.
Digdir has not stated when it expects the attack to cease. Norway’s renewed five-year security agreement with Ukraine, signed on 23 August, remains in force.
