Rethinking OT Boundaries: Sandworm's Cellular Breach of a Polish Power Plant
Zscaler, Monday, August 31st, 2026
Zscaler analyzes how Sandworm breached a Polish power plant through private cellular infrastructure long treated as inherently trusted.
Modern industrial operators are rapidly connecting remote infrastructure such as wind turbines, solar arrays, water pumps and distribution substations using cellular networks, private APNs and SD-WAN.
Historically those private cellular networks have been treated as trusted, secure and walled off from the rest of the environment.
Zscaler uses Sandworm's breach of a Polish power plant to show that assumption failing in practice, tracing how the actor reached OT systems through the cellular path. The post argues OT boundaries need rethinking and outlines the zero trust controls that mitigate this class of exposure.