CVE-2023-36844

CVE-2023-36844 is a medium-severity vulnerability (CVSS 5.3) in Juniper Networks' Junos OS, specifically impacting EX switches and SRX firewalls. This flaw, along with three others (CVE-2023-36845, CVE-2023-36846, CVE-2023-36847), was addressed by Juniper in mid-August. The details of these vulnerabilities have been made publicly available, raising concerns about potential exploitation. The US Cybersecurity and Infrastructure Security Agency (CISA) has urged organizations to secure their Juniper devices against these vulnerabilities, particularly as they are now being used in remote code execution (RCE) attacks as part of a pre-auth exploit chain. Threat actors have been found actively exploiting these vulnerabilities following the release of a proof-of-concept exploit. This series of vulnerabilities can be used in conjunction to create a critical threat of unauthenticated remote code execution by a network attacker. In response to this threat, Juniper fixed the bug tracked as CVE-2023-36844, along with several others (CVE-2023-36845, CVE-2023-36846, CVE-2023-36847, and CVE-2023-36851) in August. However, given the active exploitation of these vulnerabilities, organizations using Juniper devices are strongly advised to apply these patches immediately if they have not done so already.