SECURA: Unified Reference Architecture for Advanced Security and Trust in Safety Critical Infrastructures

In the evolving landscape of safety-critical infrastructures, ensuring the integrity and security of systems has become paramount. Building upon a previously established security architecture tailored for the railway sector, this work introduces significant enhancements that extend its applicability beyond the confines of any singular industry. Key advancements include the integration of a security heartbeat to augment safety monitoring, the implementation of a sophisticated secure update mechanism leveraging Trusted Platform Module (TPM) Enhanced Authorization (EA) policies, local Trusted Platform Module (TPM) based attestation, a cyber-resiliency watchdog in a Trusted Execution Environment (TEE) that detects compromised system components and triggers remediation actions, automated vulnerability scanning leveraging Linux Integrity Measurement Architecture (IMA) logs to check against vulnerability databases, and a formal evaluation of system integrity reporting capabilities through remote attestation.
Moreover, aiming for a universally adaptable framework, this paper proposes a reference architecture to accommodate various operational contexts. We use compartments - such as virtual machines, software containers, and RTOSes partitions - as a universal abstraction for system components, designed to be compatible with various real-time operating systemss (RTOSess), including the safety-certified PikeOS, the ACRN hypervisor, and beyond.