# Threat Analysis and Risk Assessment (TARA) Analysis of an Autonomous Emergency Braking (AEB) System
## 3 Research Methodology
### Threat and Risk Assessment  
The threat and risk assessment (TARA) phase aimed to identify and analyze the vulnerabilities of the AEB system and evaluate the risks associated with each identified threat. Initially, the selected architecture components and their interconnections were input into the Medini tool, which automatically generated a list of relevant threats.  
These threats were subsequently imported into an Excel file, where a detailed analysis was conducted to assess the risk level of each identified threat. This process adhered to a systematic approach, commencing with the identification of critical system assets and concluding with an evaluation of the feasibility and impact of each threat. Threats were categorized using STRIDE.  
For each identified threat, potential attack paths and vectors were analyzed, accompanied by a motivational assessment to understand the rationale behind an attacker's targeting of specific vulnerabilities. The impact was evaluated across multiple dimensions, including driver safety, financial repercussions, operational implications, and issues related to privacy and regulatory compliance.  
Threat severity was assessed using a quantitative scale that integrated impacts on FOPS, where we ultimately focussed on the safety risks. Additionally, the feasibility of attacks was evaluated based on the complexity and resources required to execute an effective attack. These parameters facilitated the calculation of the overall risk level for each threat, enabling the ranking of threats by criticality.  
Risk treatment decisions encompassed options such as mitigation, acceptance, avoidance, or transfer, based on the severity and feasibility of each identified threat. Mitigation measures were proposed for the high and severe safety threats to enhance security controls, with each decision documented alongside detailed justifications in the accompanying Excel file.  
Throughout this process, Medini Analyze and MTM were employed to visualize system component interactions and potential attack paths. Adhering to the guidelines of ISO/SAE 21434 ensured that all risk assessment procedures aligned with established automotive security standards.  
This approach provided a thorough understanding of AEB threats and vulnerabilities, forming the basis for implementing mitigation strategies aimed at reducing risk and enhancing system resilience. Specific mitigation strategies were developed for critical risk threats. These strategies focused on reducing the likelihood of successful attacks while minimizing the impact if they occurred.  
\begin{table}
\begin{tabular}{l c c c c c c c c c c} \hline
**Feature/Reference** & **[**11**]** & **[**12**]** & **[**6**]** & **[**7**]** & **[**16**]** & **[**14**]** & **[**8**]** & **[**17**]** & **[**18**]** & **[**15**]** & **[**19**]** \\ \hline Security & ✓ & ✓ & & & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ & \\ \hline Car Application & ✓ & ✓ & & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ \\ \hline WiFi & & & & & ✓ & & & & & & \\ \hline GPS & & & & ✓ & & ✓ & ✓ & & & & \\ \hline Machine Learning & & & & ✓ & & & & & & ✓ & \\ \hline Camera & & ✓ & ✓ & & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ \\ \hline V2X & & & & & ✓ & ✓ & & & & & ✓ \\ \hline Sensor Fusion & ✓ & ✓ & & ✓ & & & ✓ & ✓ & ✓ & & \\ \hline Radar & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ \\ \hline WSS & & & & ✓ & & & & & & & \\ \hline ADAS & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ & ✓ & & ✓ & \\ \hline \end{tabular}
\end{table}
Table 2: Occurrence of various components and key attributes in existing research papers.