OT Networks Still Need Monitoring
Brief
CERT Polska recently published a follow-up report detailing the hack of a Polish combined heat and power (CHP) plant in December 2025.
CERT Polska’s report concludes with several important recommendations, including protecting OT systems through network segmentation and monitoring traffic entering and leaving OT networks. It has now been more than 15 years since I first publicly advocated almost exactly these same two recommendations in my blog post Monitor Those Control System Networks .
One might get the impression that nothing has changed during those 15 years, but I can attest that many OT systems now have effective perimeter protection. Operators of critical infrastructure are also beginning to embrace the concept of network security monitoring for OT systems.