# Threat Analysis and Risk Assessment of a Driver Monitoring System
## 6 Risk Analysis
### STRIDE Application to System Components
#### 6.3.2 Camera Activator  
The Camera Activator is a crucial interface between the camera sensor and processing units, enabling precise image capture and data transmission. Its compromise could impact the system's ability to monitor the driver accurately and promptly. This component faces multiple threats: **Spoofing** attacks could enable an attacker to transmit falsified activation signals, leading to inappropriate system responses. **Tampering** with the activator's data or ports could cause unnecessary or misleading warnings. **Repudiation** risks occur when malicious activities involving the activator cannot be verified or traced. **Information Disclosure** is a critical concern due to handling sensitive visual data or metadata. **DoS** attacks could overwhelm the activator, disrupting its functionality. **Elevation of Privilege risks involve attackers gaining unauthorized access to its functions.**  
**Mitigation strategies include secure communication protocols (Transport Layer Security (TLS) and Secure Sockets Layer (SSL)) to ensure authenticity and integrity against Spoofing. Encryption of data, physical port security, and adherence to Automotive Open System Architecture (AUTOSAR) protocols [34] address Tampering. Implementing digital signatures for commands mitigates Repudiation by ensuring accountability; exploring blockchain for logging activation commands could provide an additional layer of tamper-evident history. Encrypting all data exchanges prevents Information Disclosure, with hybrid protocols balancing security and performance. Proxies with rate-limiting and anomaly detection (potentially AI-enhanced) ensure availability during DoS attacks. Robust authentication and AAA frameworks enforce privilege boundaries against Elevation of Privilege. Additionally, given the processing of biometric data (facial images), compliance with General Data Protection Regulation (GDPR) [35] is paramount, requiring explicit consent or other valid legal bases (vital interests and substantial public interest) and implementation of data protection measures like encryption, anonymization, minimization, and consent mechanisms.**  
**Residual risks and challenges remain. Spoofing mitigations rely on certificate management, which is complex and potentially latency-inducing in embedded systems [36]. Tampering mitigations like physical security increase costs, while AUTOSAR integration can be resource-intensive. Repudiation depends on secure key storage (for signatures) or the overheads and complexities associated with potential blockchain solutions. Information Disclosure mitigations (encryption) may require hardware acceleration for real-time performance, and ensuring robust encryption under varying loads is an open question. DoS defenses are not infallible against sophisticated attackers. Elevation of Privilege controls depend on proper configuration and maintenance. Overall, trade-offs between security, cost, and performance, especially in low-cost models, require careful evaluation and potentially lightweight security protocols.**