POSEIDON: An Integrated Cybersecurity Framework for Maritime Systems with Empirical Validation

Abstract The maritime sector faces increasing cyber threats that compromise the operational safety of ships. This study introduces POSEIDON (Procedures, Operations and Standards for Comprehensive Detection for Naval Cyber Defence), a modular process-based framework that operationalises international standards (ISO/IEC 27001, NIST CSF, IEC 62443 and IMO guidelines) into verifiable procedures tailored to the naval IT/OT environment. Through a case study on a dual-purpose vessel, its empirical deployment in the Data Distribution Unit (DDU) proved effective: critical vulnerabilities were reduced by 57%, phishing success dropped by 85.7%, and critical intrusions were contained within approximately 30 minutes. These outcomes were accompanied by measurable improvements in mean time to detection (MTTD), technology readiness level (TRL), and the crew’s cybersecurity culture under operational stress. The study makes five key contributions: it presents a modular framework validated in real operational environments; provides reproducible validation supported by robust quantitative metrics; integrates cybersecurity requirements throughout the TRL model and extends it to TRL-10 for secure decommissioning; incorporates cyberpsychology as a pillar of organisational resilience; and demonstrates scalability and transferability to other vessels and critical infrastructures. Collectively, the findings establish POSEIDON as a comprehensive and transferable benchmark for next-generation maritime cybersecurity aligned with international standards.