Description

Approximately 1,450 exposed pfSense instances face vulnerabilities stemming from command injection and cross-site scripting (XSS) flaws, posing a risk of potential remote code execution. pfSense, renowned for its open-source firewall and router capabilities, offers extensive customization but recently faced security concerns. Discovered in mid-November by SonarSource’s researchers and impacting pfSense 2.7.0 and earlier, as well as pfSense Plus 23.05.01 and older, the flaws include CVE-2023-42325 (XSS), CVE-2023-42327 (XSS), and CVE-2023-42326 (command injection). The severity is heightened by CVE-2023-42326's (command injection) CVSS score of 8.8, allowing attackers to execute commands with root privileges. This vulnerability arises from inadequate validation in configuring network interfaces, particularly impacting the "gifif" parameter, enabling malicious command injections. Successful exploitation requires chaining flaws, needing access to an account with interface editing permissions. XSS flaws (CVE-2023-42325 or CVE-2023-42327) could precede executing malicious JavaScript in an authenticated user’s browser, gaining control over the pfSense session. Netgate responded promptly upon receiving reports on July 3, 2023, issuing security updates on November 6 (pfSense Plus 23.09) and November 16 (pfSense CE 2.7.1). Despite patches being available for a month, approximately 1,450 vulnerable instances persist, making up 92.4% of directly discoverable instances on Shodan. While immediate compromise isn’t imminent, the exposure significantly broadens the attack surface. Considering pfSense's use by large enterprises, the risk is amplified. Attackers exploiting these vulnerabilities could breach data, access sensitive resources, and move laterally within compromised networks, posing severe risks to affected organizations.