Defending Against an Active Threat to Siemens S7 Series PLCs

CISA advisories describe active cyber threats against critical infrastructure, including AI-assisted reconnaissance and exploitation of internet-exposed Siemens S7 PLCs, Iranian-affiliated targeting and disruption of PLCs across multiple vendors, pro-Russia hacktivist attacks against OT/ICS, Russian exploitation of vulnerable networking devices, and LAUNDRY BEAR exploitation of Zimbra Collaboration Suite (CVE-2025-66376). Guidance emphasizes removing OT and network devices from direct internet exposure, patching, access control, segmentation, monitoring, threat hunting, secure PLC/ladder-logic