Background: The maritime industry, vital for global trade, faces escalating cyber threats in 2025. Critical port infrastructures are increasingly vulnerable due to rapid digitalization and the integration of IT and operational technology (OT) systems. Methods: Using 112 incidents from the Maritime Cyber Attack Database (MCAD, 2020–2025), we developed a novel quantitative risk assessment model based on a Threat-Vulnerability-Impact (T-V-I) framework, calibrated with MITRE ATT&CK techniques and validated against historical incidents. Results: Our analysis reveals a 150% rise in incidents, with OT compromise identified as the paramount threat (98/100 risk score). Ports in Poland and Taiwan face the highest immediate risk (95/100), while the Panama Canal is assessed as the most probable next target (90/100). State-sponsored actors from Russia, China, and Iran are responsible for most high-impact attacks. Conclusions: This research provides a validated, data-driven framework for prioritizing defensive resources. Our findings underscore the urgent need for engineering-grade solutions, including network segmentation, zero-trust architectures, and proactive threat intelligence integration to enhance maritime cyber resilience against evolving threats.