CISA (CISA) - Defending Against an Active Threat to Siemens S7 Series PLCs
Executive summary Note: This advisory relates to an active threat to Siemens S7 Series programmable logic controllers (PLCs). However, ongoing PLC targeting activity is broader than Siemens PLCs. All PLC owners and operators should apply relevant mitigations to reduce the risk to their devices and systems. The Siemens-specific content in this advisory should be understood and applied as one subset of the wider threat landscape. Top Mitigations - Inventory all Siemens S7 Series programmable logic controllers (PLCs) - Apply critical security patches - Ensure PLCs are not accessible from the Internet - Strengthen access controls - Monitor for unauthorized activity - Harden PLC services, protocols, and ladder logic…