CVE-2025-34080 identifies a reflected Cross-Site Scripting (XSS) vulnerability in the Contec Co.,Ltd. CONPROSYS HMI System (CHS), specifically affecting versions prior to 3.7.7. The vulnerability arises from improper neutralization of input data in the getqsetting.php script, which is part of the web interface used to manage and monitor industrial control systems. Reflected XSS occurs when malicious input sent via a crafted URL or request is immediately echoed back in the HTTP response without adequate sanitization or encoding, enabling execution of arbitrary JavaScript code in the victim's browser. This can lead to session hijacking, theft of authentication tokens, redirection to malicious sites, or unauthorized actions performed with the victim’s privileges. The CVSS 4.0 vector indicates the attack requires no privileges and no authentication, with low attack complexity, but does require user interaction (e.g., clicking a malicious link). The vulnerability affects confidentiality and integrity by potentially exposing sensitive session data and enabling unauthorized commands but does not directly impact availability. No public exploits have been reported yet, but the presence of this vulnerability in industrial HMI systems is concerning due to the critical nature of these systems in operational technology environments. The lack of a patch link suggests that a fixed version (3.7.7 or later) is either newly released or pending, emphasizing the need for timely updates. The vulnerability is tracked under CWE-79, a common and well-understood web application security weakness.

For European organizations, particularly those in manufacturing, energy, and critical infrastructure sectors using CONPROSYS HMI systems, this vulnerability could enable attackers to compromise operator sessions and manipulate industrial control interfaces. This may result in unauthorized control commands, data leakage, or disruption of industrial processes, potentially causing safety hazards or operational downtime. The reflected XSS could also serve as an initial foothold for more advanced attacks, including lateral movement within OT networks. Given the increasing integration of IT and OT environments in Europe, exploitation could bridge cyber threats into physical process disruptions. The medium severity reflects moderate risk, but the critical nature of affected systems elevates the importance of remediation. Organizations failing to address this vulnerability may face regulatory scrutiny under EU cybersecurity directives such as NIS2, especially if incidents lead to service interruptions or data breaches.

1. Upgrade the CONPROSYS HMI System to version 3.7.7 or later as soon as the patch is available to ensure the vulnerability is fixed. 2. Until patching is possible, implement strict input validation and output encoding on the getqsetting.php endpoint to neutralize malicious scripts. 3. Deploy Web Application Firewalls (WAFs) with rules specifically targeting XSS attack patterns to block malicious requests. 4. Educate users and operators to avoid clicking on suspicious links or interacting with untrusted sources that could trigger reflected XSS. 5. Conduct regular security assessments and penetration testing focused on web interfaces of industrial control systems. 6. Segment and isolate HMI systems from general IT networks to limit exposure. 7. Monitor logs and network traffic for unusual activity indicative of attempted XSS exploitation. 8. Collaborate with Contec support for guidance and timely updates on vulnerability management.