Locked Shields 2025 –NATO Cyber Defence Exercise

The Ministry of National Defence participated, between May 5 and 9, 2025, in Locked Shields 2025, the most complex NATO-led cyber security and defence exercise. The event took place in Romania, for the first time, at the Polytechnic University of Bucharest, and involved military and civilian specialists acting in the fields of cyber security and defence.

Locked Shields is organized annually by the NATO Cooperative Cyber ​​Defence Cooperation Centre of Excellence (CCDCOE) in Tallinn, Estonia, and provides a realistic training environment for testing response capabilities to various and evolving cyber threats. This year's edition brought together nearly 4,000 civilian and military experts from 41 Allied and Partner nations, grouped into 17 multinational Blue Teams, each tasked with protecting simulated national critical infrastructure in a scenario consisting of over 9,000 complex cyber attacks.

Romania is in its fifth participation, represented by the Cyber ​​Defence Command, which made up a joint team with Portugal and the Republic of Moldova, consisting in approximately 260 specialists from institutions acting in the National Defence, Public Order and Security System, the National Cyber ​​Security Directorate, academia, as well as private companies with expertise in the field of cyber security.

Participants were requested to manage and respond in real time to a wide range of cyber incidents, reflecting current global challenges, such as protecting essential services and critical infrastructures fundamental to the functioning of modern societies, including energy networks, water distribution and purification systems, satellite, communication, 5G and defense services.

Locked Shields stands out from other exercises due to its complex and multidimensional nature, requiring teams not only to respond technically to cyber attacks, but also to manage public communication, provide legal advice and make strategic decisions, all conducted while experiencing time pressure and intense stress.

By actively engaging in this exercise, Romania reconfirms its firm commitment to strengthening collective cyber security within NATO and developing a robust, interoperable and resilient national cyber defence capability in the face of modern threats

The Press Office