Summary
Critical Infrastructure Sectors . This advisory details the tactics, techniques, and procedures, and indicators of compromise (IOCs) linked to threat actors deploying LummaC2 malware. This malware poses a serious threat, capable of infiltrating networks and exfiltrating sensitive information, to vulnerable individuals’ and organizations’ computer networks across U.S. critical infrastructure sectors. As recently as May 2025, threat actors have been observed using LummaC2 malware, underscoring the ongoing threat. The advisory includes IOCs tied to infections from November 2023 through May 2025. Organizations are strongly urged to review the advisory and implement the recommended mitigations to reduce exposure and impact.