Operation Sword 26: Multinational Cyber Defense Exercise in Estonia

• •Immediate Response 2026 involved U.S. and NATO forces in a cyber defense exercise.
• •The exercise simulated attacks on critical infrastructure, enhancing operational readiness.
• •Real-time scenario adjustments were made by the white cell to ensure realistic training.

In May 2026, a multinational cyber defense exercise named Immediate Response 2026 took place in Estonia, involving U.S. and NATO Allied and partner forces. The exercise simulated cyber threats to critical infrastructure, including a model railroad system representing operational technology systems. Participants practiced defending against cyber threats and enhancing network security and interoperability. The exercise is part of the broader Operation Sword 26, which spans eight countries in the High North and Baltic region. The white cell, responsible for scenario development, guided training objectives and adjusted scenarios in real-time to create a realistic environment for cyber operators. This event is crucial for improving collaborative defensive cyber operations among allied forces.