Ransomware on cyber-physical systems: Taxonomies, case studies, security gaps, and open challenges

Ransomware attacks have emerged as one of the most significant cyberthreats faced by organizations worldwide. In recent years, ransomware has also started to target critical infrastructure and Cyber-Physical Systems (CPS) such as industrial control systems, smart grids, and healthcare networks. The unique attack surface and safety-critical nature of CPS introduce new challenges in defending against ransomware. This paper provides a comprehensive overview of ransomware threats to CPS. We propose a dual taxonomy to classify ransomware attacks on CPS based on infection vectors, targets, objectives, and technical attributes. Through an analysis of 10 real-world incidents, we highlight attack patterns, vulnerabilities, and impacts of ransomware campaigns against critical systems and facilities. Based on the insights gained, we identify open research problems and future directions to improve ransomware resilience in CPS environments.