The Cybersecurity and Infrastructure Security Agency (CISA) has issued a critical warning to federal agencies, urging them to promptly secure Juniper devices against a pre-auth remote code execution (RCE) exploit chain.
Four vulnerabilities, including CVE-2023-36844, CVE-2023-36845, CVE-2023-36846, and CVE-2023-36847, have been actively exploited, as confirmed by Juniper’s Security Incident Response Team (SIRT). The urgency arises from detection efforts by the ShadowServer threat monitoring service, which observed exploitation attempts shortly after Juniper released security updates.
Furthermore, over 10,000 Juniper devices, primarily from South Korea, have exposed J-Web interfaces, making immediate upgrades crucial to eliminate the attack vector. Administrators are advised to swiftly secure their devices by upgrading JunOS to the latest release or, at a minimum, restrict internet access to the J-Web interface.
At the same time, CISA’s Known Exploited Vulnerabilities Catalog now designates these Juniper vulnerabilities as “frequent attack vectors for malicious cyber actors,” emphasizing their significant risk. In response, U.S. Federal Civilian Executive Branch Agencies must secure Juniper devices within the next four days, aligning with a binding operational directive (BOD 22-01) issued a year ago.
Additionally, while primarily targeting federal agencies, CISA strongly encourages all organizations, including private companies, to prioritize patching these vulnerabilities and enhance the security of Internet-exposed networking equipment.