Denmark raises threat level for destructive cyberattacks to high

The Danish Agency for Societal Security has raised the threat level for destructive cyberattacks against Denmark from medium to high, saying it considers it likely that Russia will attempt to carry out such attacks against the country.

The heightened assessment follows an assessment by the Danish Defence Intelligence Service (FE) that Russia will intensify its hybrid warfare against the West and NATO in the coming months.

According to the agency, the Danish Security and Intelligence Service (PET) has also identified concrete Russian planning and preparations for sabotage targeting Denmark.

“Destructive cyberattacks can potentially affect critical societal functions and have an impact on authorities, businesses and citizens,” said Laila Reenberg, director of the Danish Agency for Societal Security.

She is urging authorities and companies responsible for critical infrastructure in particular to take measures corresponding to the heightened threat.

A destructive cyberattack could, for example, attempt to delete data in a way that prevents it from being recovered or manipulate systems that control physical infrastructure.

According to the agency, a small Danish waterworks was targeted in late 2024 when pro-Russian hackers with links to the Russian state manipulated water pressure. As a result, 450 households were left without water for a period of time.

The agency also said it is aware of several attempted destructive cyberattacks in European NATO countries over the past year.

One example was an attack targeting Poland’s energy sector in December 2025, which was prevented. The Polish government has attributed the attack to Russia.