A Demonstration of MBSEsec Applied to Securing Cyber-Physical System Communications

The Engineering community is adopting a Digital Engineering approach enabled by Model-Based Systems Engineering (MBSE) as an effective tool for designing complex systems. As technology continues to rapidly advance, security risk mitigation and requirements engineering is becoming a prominent and important factor in the cybersecurity domain. MBSEsec is a security-focused MBSE method using SysML to develop a system architecture that highlights security design considerations. The modeling process used in the MBSEsec method facilitates security requirements and controls elicitation through a structured workflow of specific systems modeling activities. This work illustrates the application of MBSEsec to securing vehicle network transport protocols. The discovery and validation of new exploits that take advantage of vulnerabilities in the data-link layer of the protocol highlights the need to elicit better security requirements for cyber physical systems (CPS). This paper addresses the three pillars of MBSE to secure network architecture, and models five transport protocol vulnerabilities that have been validated and exploited. Using MBSEsec we create security requirements, identify system assets, model threats and risks, and generate security controls for network transport protocols. This work uses heavy vehicle network transport protocol, J1939, as the System of Interest. Using the J1939 network as the SOI for this work allows the models to be supported by and validated with on-vehicle testing. This work contributes a survey of modeling approaches for secure system design, a detailed application of MBSEsec to a CPS network, and illustrates a recommended addition of a new element 'attacker' to the MBSEsec profile. This addition, as well as a detailed threat analysis through attack modeling, enables the generation of more accurate, complete, and effective security requirements for preexisting systems.