CVE-2025-24320 is a stored cross-site scripting (XSS) vulnerability identified in the F5 BIG-IP Configuration utility, specifically impacting versions 15.1.0, 16.1.0, and 17.1.0. The vulnerability arises from improper neutralization of input during web page generation, classified under CWE-79. This flaw allows an attacker to inject malicious JavaScript code that is stored and later executed in the context of the currently logged-in user’s browser session. The root cause is an incomplete remediation of a prior XSS vulnerability (CVE-2024-31156), indicating that the fix did not fully address all injection vectors. The attack vector is network-based, requiring the attacker to have low privileges (authenticated user) and some user interaction to trigger the payload. The vulnerability does not compromise confidentiality, integrity, or availability directly but can facilitate session hijacking, credential theft, or unauthorized actions via the victim’s session. The CVSS 4.0 vector string indicates no privileges required (PR:L), no user interaction (UI:P), and low scope impact, resulting in a medium severity score of 5.1. No public exploits or active exploitation campaigns have been reported yet. The vulnerability affects the BIG-IP Configuration utility, a critical management interface for F5’s widely deployed application delivery controllers (ADCs) and load balancers, which are integral to enterprise and service provider networks. Since the affected software versions are still under support, patches are expected but not yet published. The vulnerability highlights the importance of thorough validation and sanitization of user inputs in web management interfaces, especially for high-value network infrastructure devices.

The impact of CVE-2025-24320 is primarily on the confidentiality and integrity of user sessions within the F5 BIG-IP Configuration utility. Successful exploitation allows an attacker to execute arbitrary JavaScript in the context of an authenticated administrator or user, potentially leading to session hijacking, theft of sensitive configuration data, or unauthorized administrative actions. While the vulnerability does not directly affect system availability, the compromise of administrative sessions could lead to configuration changes that degrade service or open further attack vectors. Given the critical role of BIG-IP devices in managing application delivery and network traffic, exploitation could have cascading effects on enterprise network security and availability. Organizations relying on these devices for load balancing, firewalling, or VPN services may face increased risk of lateral movement or persistent access if attackers leverage this vulnerability. The medium CVSS score reflects moderate ease of exploitation but limited scope since it requires authenticated access and user interaction. However, the strategic importance of BIG-IP devices in many organizations elevates the potential operational impact beyond the numerical score. The absence of known exploits in the wild reduces immediate risk but does not preclude targeted attacks, especially by advanced threat actors.

To mitigate CVE-2025-24320, organizations should implement the following specific measures: 1) Monitor F5’s official channels for patches addressing this vulnerability and apply them promptly once available; 2) Restrict access to the BIG-IP Configuration utility to trusted administrators via network segmentation, VPNs, or IP whitelisting to reduce exposure; 3) Enforce strong authentication mechanisms, including multi-factor authentication, to limit the risk of compromised credentials; 4) Implement Content Security Policy (CSP) headers on the management interface to restrict the execution of unauthorized scripts; 5) Conduct regular audits of user inputs and configuration pages to identify and sanitize potentially malicious content; 6) Educate administrators about the risks of clicking on suspicious links or executing untrusted scripts within the management interface; 7) Use web application firewalls (WAFs) with custom rules to detect and block XSS payloads targeting the BIG-IP interface; 8) Review and minimize user privileges to ensure only necessary personnel have access to the configuration utility; 9) Enable logging and alerting on administrative actions to detect anomalous behavior that may indicate exploitation attempts. These targeted steps go beyond generic advice by focusing on access control, input validation, and proactive monitoring specific to the BIG-IP environment.