ANSI/ISA 62443-4-2:2018

ANSI/ISA-62443-4-2-2018, Security for Industrial Automation and Control Systems – Part 4-2: Technical Security Requirements for IACS Components, Second Printing, specifies cybersecurity requirements for components within industrial automation and control systems (IACS), covering embedded devices, host devices, network devices and software applications. This standard organizes security into seven foundational areas: identification and authentication, use control, system integrity, data confidentiality, restricted data flow, timely response to events and resource availability. Components are assigned security capability levels that match their ability to address threats of varying sophistication. Technical requirements include enforcing least privilege access, supporting multifactor authentication, protecting against malicious code, validating inputs, managing secure updates, providing tamper resistance and maintaining detailed audit logs with synchronized timestamps. Components may rely on compensating countermeasures when native capabilities are lacking, enabling secure integration within larger systems. This framework aligns component design and integration with control systems' operational demands, emphasizing availability, integrity and confidentiality while preserving essential functions and supporting risk-based security approaches.