Defending Against an Active Threat to Siemens S7 Series PLCs

CISA advisories describe active, state-sponsored and criminal cyber threats affecting critical infrastructure, industrial control systems, internet-exposed PLCs, networking devices, Zimbra Collaboration Suite, and ransomware-vulnerable organizations. Key activity includes exploitation of Siemens and other PLCs by Iranian-affiliated and other actors, Russian state-supported exploitation of Zimbra (CVE-2025-66376), Russian targeting of poorly configured networking devices, China-nexus covert proxy networks, and Gunra ransomware double extortion. Recommended defenses include removing OT devicesから