How is a Hardware Security Module (HSM) used in automotive ECUs?

HSM provides hardware-based security functions: Secure key storage in protected memory inaccessible to main processor, cryptographic acceleration (AES, RSA, ECC), secure boot verification (validating firmware authenticity before execution), random number generation (TRNG), and secure debug access control. HSM implementation involves defining security levels for different operations, key hierarchy design, lifecycle management (manufacturing, field, end-of-life), firmware update procedures for HSM, and integration with application security requirements. Automotive HSMs meet SHE (Secure Hardware Extension) or EVITA specifications. HSM is essential for SecOC, secure boot, and protected diagnostic functions.