A Systematic Literature Review of Automotive TARA Methodologies: Classification and Compliance with ISO/SAE 21434

The increase in advanced functionalities has led to a rapid rise in both external connectivity and system complexity, thereby amplifying the impact of cybersecurity threats on vehicle safety. As a result, the automotive industry is now required to conduct Threat Analysis and Risk Assessment (TARA) in full compliance with UN Regulation No. 155 and the requirements of ISO/SAE 21434. This study adopts the Systematic Literature Review (SLR) methodology and establishes three research questions, search keywords, and inclusion/exclusion criteria to ensure a systematic and objective selection of relevant literature. Through comprehensive searches across major global academic databases, including IEEE Xplore, SpringerLink, ScienceDirect, Scopus and WoS and a screening process, a final set of 15 representative studies on automotive TARA was identified. Each selected study was classified into one of four categories based on the nature of the challenges it aimed to address: (1) high demand for human and time resources, (2) insufficient consideration of safety, (3) insufficient lifecycle coverage, and (4) inadequate evaluation criteria. Furthermore, the degree of compliance with the ISO/SAE 21434 TARA requirements was analyzed for each study. These findings provide foundational insights to support stakeholders in the automotive industry in selecting or developing TARA methodologies suited to their organizational contexts, and offer implications for future improvements to international standards.