As digital systems increasingly control the world’s most powerful machines, software failures have become a silent but deadly threat—sometimes with fatal consequences. This DEFCON presentation dives deep into maritime and military incidents where software errors, automation missteps, and human-computer interface flaws have led to catastrophic outcomes. Reviewing the USS Yorktown’s infamous “Smart Ship” crash and the USS Vincennes’ tragic misidentification of a civilian airliner, we dissect how code, configuration, and design choices can escalate into life-or-death situations at sea. We’ll also draw parallels to high-profile aviation incidents like the Boeing 737 Max and F-35, illustrating common threads in software assurance failures across domains. We’ll walk through how a subtle software flaw could be exploited to disrupt critical vessel operations, and what this means for the future of maritime cybersecurity. Attendees will gain insight into the technical, organizational, and ethical challenges of securing mission-critical systems, and leave with practical takeaways for hackers, engineers, and policymakers seeking to prevent the next digital disaster on the high seas. With 25 years of experience in the maritime sector, Michael is dedicated to ensuring the safety and security of the global Maritime Transportation System (MTS). A retired US Coast Guard Officer, he has conducted numerous safety and compliance inspections, investigated high-profile marine casualties, and established a cybersecurity program at USCG Cyber Command. Previously, as a Business Information Security Officer for Royal Caribbean Group, Michael developed strategies to maintain the cybersecurity and regulatory compliance of the company's global cruise fleet. Holding a B.S. in Computer Science and an M.S. in Telecommunications, he currently serves as ABS Consulting's Maritime Cybersecurity Director. In this role, he specializes in managing cyber risks, implementing technical solutions, shaping policy and governance, providing expert advisory services, and designing custom solutions to meet maritime regulatory requirements and best practices. Austin Reid is a senior consultant at ABS Consulting specializing in securing maritime operational technology with 10 years experience in the Maritime sector from breakbulk, automated container terminal ops, and securing critical vessel systems for all types of ships. He is also a hacker, and security researcher specializing in maritime navigation control systems.