CVE-2025-41748 is a cross-site scripting (XSS) vulnerability categorized under CWE-79, affecting the Phoenix Contact FL SWITCH 2005 device's web-based management interface (WBM), specifically the pxc_Dot1xCfg.php page. The vulnerability arises from improper neutralization of input during web page generation, allowing an attacker to inject malicious scripts. An unauthenticated remote attacker can exploit this by crafting a malicious URL that, when clicked by an authenticated user, executes arbitrary JavaScript within the context of the device's web application. This can lead to unauthorized changes to device configuration parameters exposed via the WBM. The vulnerability does not grant access to operating system internals or privileged functions, limiting the attacker's reach to the web application's configuration context. The session cookie is protected by the httpOnly flag, preventing session hijacking through script access. The attack requires user interaction (clicking the malicious link) but no prior authentication or elevated privileges, making it relatively easy to exploit in targeted phishing or social engineering scenarios. The vulnerability has a CVSS 3.1 base score of 7.1, indicating high severity due to its network attack vector, low attack complexity, no privileges required, user interaction required, and impact on confidentiality, integrity, and availability within the scope of the web application. No patches or known exploits are currently available, and the vulnerability was published on December 9, 2025. The affected product is commonly used in industrial automation and critical infrastructure environments, where configuration integrity is crucial for operational safety and reliability.

For European organizations, especially those in industrial automation, manufacturing, energy, and critical infrastructure sectors, this vulnerability poses a significant risk. Exploitation could allow attackers to manipulate network switch configurations remotely by deceiving authenticated users, potentially disrupting network operations, causing misconfigurations, or creating backdoors for further attacks. Although the vulnerability does not allow direct system-level compromise or session hijacking, altering device parameters can degrade network availability and integrity, impacting operational continuity and safety. Given the widespread use of Phoenix Contact products in European industrial environments, successful exploitation could lead to operational downtime, safety incidents, or compliance violations with regulations such as NIS2. The requirement for user interaction means targeted phishing or social engineering campaigns could be effective attack vectors, increasing the risk for organizations with less mature security awareness programs. The absence of patches increases exposure time, necessitating immediate compensatory controls to mitigate risk.

1. Implement strict network segmentation to isolate management interfaces of FL SWITCH 2005 devices from general user networks, reducing exposure to unauthenticated attackers. 2. Enforce multi-factor authentication (MFA) and strong access controls on web-based management interfaces to limit authenticated user access and reduce the risk of successful social engineering. 3. Conduct targeted security awareness training focusing on phishing and social engineering to reduce the likelihood of users clicking malicious links. 4. Monitor network traffic and web server logs for suspicious requests targeting pxc_Dot1xCfg.php or unusual parameter changes indicative of exploitation attempts. 5. Employ web application firewalls (WAF) with custom rules to detect and block XSS payloads targeting the vulnerable endpoint. 6. Regularly audit device configurations for unauthorized changes and maintain backups to enable rapid restoration. 7. Engage with Phoenix Contact for updates and apply patches promptly once available. 8. Consider deploying endpoint protection solutions that can detect and block malicious scripts executed in browsers. 9. Restrict outbound email and web access to limit attacker communication channels and reduce phishing effectiveness. 10. If possible, disable or restrict access to the vulnerable web management interface until a patch is available.