Secure Software Development Lifecycle (SSDLC)

The increased numbers in demand of software-defined vehicles (SDVs), over-the-air (OTA) updates, and V2X communication has transformed / been transforming the automotive industry. Cybersecurity is no longer just a paper work, it's a fundamental requirement of vehicle safety and performance.

Secure Software Development Lifecycle (SSDLC) is an approach that integrates security considerations at every stage of software development, ensuring that vulnerabilities are identified and removed before they can be exploited.

The Need for SSDLC in Automotive Software

Modern vehicles are no longer just mechanical systems; they are complex, interconnected electronic ecosystems with millions of lines of code running on multiple Electronic Control Units (ECUs). Features such as:

• Advanced Driver Assistance Systems (ADAS)
• General Safety Regulations (GSR)
• Several control units (ECM)
• Autonomous driving
• Vehicle-to-Everything (V2X) Communication

Regulatory & Compliance Drivers

Legislation based, Automotive software must comply with cybersecurity standards such as:

• ISO/SAE 21434 – Automotive Cybersecurity Engineering
• UNECE WP.29 R155 & R156 – Cybersecurity & Software Update Management
• NIST Cybersecurity Framework – Best practices for security governance
• AUTOSAR Secure Software Development – Guidelines for embedded security

Key Stages of SSDLC in Automotive Engineering

SSDLC follows the traditional Software Development Lifecycle (SDLC) but incorporates security controls at every stage.

• Define security requirements based on functional safety (ISO 26262) and cybersecurity (ISO/SAE 21434).
• Conduct Threat Analysis and Risk Assessment (TARA) to determine potential attack paths.
• Identify high-risk ECUs (e.g., gateways, infotainment, telematics, ADAS systems).
• Design the software according to secure design principles.
• Implement hardware security modules (HSMs) for secure operations.
• Define access control policies from ECU to ECU.
• Use secure coding standards.
• Use static code analysis tools.
• Perform penetration testing to simulate real-world attacks.
• Implement continuous security testing.

As vehicles become more software-driven, cybersecurity must be a priority