Yesterday, the Cybersecurity and Infrastructure Security Agency (CISA), the FBI, the National Security Agency (NSA), U.S. Cyber Command Cyber National Mission Force, the U.S. Department of the Treasury, the Australian Cyber Security Centre (ACSC), the Canadian Centre for Cyber Security (CCCS), and the United Kingdom’s National Cyber Security Centre (NCSC) published a joint Cybersecurity Advisory (CSA) to highlight continued malicious cyber activity by advanced persistent threat (APT) actors affiliated with the Iranian Government’s Islamic Revolutionary Guard Corps (IRGC).

This advisory updates joint CSA Iranian Government-Sponsored APT Cyber Actors Exploiting Microsoft Exchange and Fortinet Vulnerabilities in Furtherance of Malicious Activities (AA22-257A). According to the advisory, “Since the initial reporting of this activity in the FBI Liaison Alert System (FLASH) report APT Actors Exploiting Fortinet Vulnerabilities to Gain Access for Malicious Activity from May 2021, the authoring agencies have continued to observe these IRGC-affiliated actors exploiting known vulnerabilities for initial access. In addition to exploiting Fortinet and Microsoft Exchange vulnerabilities, the authoring agencies have observed these APT actors exploiting VMware Horizon Log4j vulnerabilities for initial access. The IRGC-affiliated actors have used this access for follow-on activity, including disk encryption and data extortion, to support ransom operations.” These Iranian threat actors are actively targeting a large number of organizations, including entities across multiple U.S. critical infrastructure sectors as well as Australian, Canadian, and United Kingdom organizations. The authoring agencies assess the actors are exploiting known vulnerabilities on unprotected networks rather than targeting specific targeted entities or sectors.

Additionally, the advisory provides observed tactics, techniques, and indicators of compromise (IOCs) that the authoring agencies assess are likely associated with this IRGC-affiliated APT. Mitigation recommendations are provided for network defenders. To report suspicious or criminal activity related to information found in advisory, contact your local FBI field office, or the FBI’s 24/7 Cyber Watch (CyWatch) at (855) 292-3937, or by e-mail at CyWatch@fbi.gov. If you have any further questions, or to request incident response resources or technical assistance related to these threats, contact CISA at CISAServiceDesk@cisa.dhs.gov. Access the full advisory at CISA.