Bulletins

US CERT
04/21/2026
Defending against china-nexus covert networks of compromised devices executive summary Defending against China-nexus covert networks of compromised devices Explaining the widespread shift in tactics, techniques and procedures (TTPs) towards networks of compromised infrastructure, and how to defend against it Summary With support from the UK Cyber League, this advisory has …
US CERT
04/06/2026
Advisory at a Glance Title Iranian-Affiliated Cyber Actors Exploit Programmable Logic Controllers Across US Critical Infrastructure Original Publication April 7, 2026 Executive Summary Iran-affiliated advanced persistent threat (APT) actors are conducting exploitation activity targeting internet-facing operational technology (OT) devices, including programmable logic controllers (PLCs) manufactured by Rockwell Automation/Allen-Bradley. This activity …
US CERT
12/05/2025
Summary Note: This joint Cybersecurity Advisory is being published as an addition to the Cybersecurity and Infrastructure Security Agency (CISA) May 6, 2025, joint fact sheet Primary Mitigations to Reduce Cyber Threats to Operational Technology and European Cybercrime Centre’s (EC3) Operation Eastwood, in which CISA, Federal Bureau of Investigation (FBI), …
US CERT
09/22/2025
Advisory at a Glance Executive Summary CISA began incident response efforts at a U.S. federal civilian executive branch (FCEB) agency following the detection of potential malicious activity identified through security alerts generated by the agency’s endpoint detection and response (EDR) tool. CISA identified three lessons learned from the engagement that …
US CERT
08/25/2025
Executive summary People’s Republic of China (PRC) state-sponsored cyber threat actors are targeting networks globally, including, but not limited to, telecommunications, government, transportation, lodging, and military infrastructure networks. While these actors focus on large backbone routers of major telecommunications providers, as well as provider edge (PE) and customer edge (CE) …
US CERT
07/29/2025
Summary The Cybersecurity and Infrastructure Security Agency (CISA) and U.S. Coast Guard (USCG) are issuing this Cybersecurity Advisory to present findings from a recent CISA and USCG hunt engagement. The purpose of this advisory is to highlight identified cybersecurity issues, thereby informing security defenders in other organizations of potential similar …
US CERT
07/21/2025
Summary Note: This joint Cybersecurity Advisory is part of an ongoing #StopRansomware effort to publish advisories for network defenders that detail various ransomware variants and ransomware threat actors. These #StopRansomware advisories include recently and historically observed tactics, techniques, and procedures (TTPs) and indicators of compromise (IOCs) to help organizations protect …
US CERT
06/12/2025
Summary The Cybersecurity and Infrastructure Security Agency (CISA) is releasing this advisory in response to ransomware actors leveraging unpatched instances of a vulnerability in SimpleHelp Remote Monitoring and Management (RMM) to compromise customers of a utility billing software provider. This incident reflects a broader pattern of ransomware actors targeting organizations …