Abstract Russia has long been considered an effective actor in the cyber domain. Following its full-scale invasion of Ukraine on 24 February 2022, concerns grew over a surge in cyber-attacks to aid its military and pressure Europe. While Ukraine showed unexpected cyber resilience and the immediate military-operational impact was limited, Russia’s cyber campaign evolved, intensifying cyber operations on the European Union ( EU ) and its member states for broader politico-strategic objectives. In response, the EU and European countries swiftly enhanced support for Ukraine and bolstered collective cyber defences. The EU ’s cyber diplomacy proved a crucial catalyst, activating pre-existing tools, coordinating responses from private actors and accelerating the upgrade of its strategic and legislative frameworks on cyber security. These multi-faceted efforts, building on pre-war initiatives, have provided a rapid yet durable response to the conflict, significantly strengthening the long-term resilience of European societies and institutions in the face of Russia’s persistent cyber interferences.