Securing Legacy Communication Networks via Authenticated Cyclic Redundancy Integrity Check

Integrating modern communication technologies into legacy systems, such as Industrial Control Systems and in-vehicle networks, invalidates the assumptions of isolated and trusted operating environments. Security incidents like the 2015 Ukraine power grid attack and the 2021 compromise of a U.S. water treatment facility demonstrate how increased interconnectivity, paired with insufficient security measures, expose these critical systems to cyber threats, posing risks to national and public safety. These attacks were favored by the lack of proper message authentication, highlighting its importance as a primary countermeasure to enhance system security. Solutions proposed in the literature remain largely unadopted in practice due to challenges such as preserving backward compatibility, additional hardware requirements, and limited computational resources on legacy devices. Moreover, many solutions are protocol-specific, necessitating complex and costly multiple implementations in heterogeneous systems. In this paper, we propose Authenticated Cyclic Redundancy Integrity Check (ACRIC), a novel security mechanism that overcomes these limitations by leveraging a cryptographic computation of the existing Cyclyic Redundancy Check (CRC) field to ensure message integrity protection and authentication. ACRIC preserves backward compatibility without requiring additional hardware and is protocol agnostic. This makes it applicable across various systems, suitable for diverse legacy network protocols including point-to-point and broadcast communications. Experimental results, supported by formal verification and real-world testing, demonstrate that ACRIC offers robust security with minimal transmission overhead (<< 1 ms). This proves ACRIC's practicality, cost-effectiveness, and suitability for real-world adoption.