ThreatsIndustrial, OT & IoTCriticalCISA ICS Advisory ICSA-26-258-01: Applying IEC 62443 Security Levels & Purdue Model IsolationCISA ICS-CERT advisory ICSA-26-258-01 prompts urgent implementation of IEC 62443-3-2 zone segmentation and Purdue Model controls in industrial networks.Daniel Okafor·16 Sep 2026, 19:55 IST·11 min read