CVE-2025-34080 identifies a reflected Cross-Site Scripting (XSS) vulnerability in the Contec Co.,Ltd. CONPROSYS HMI System (CHS), specifically in the getqsetting.php functionality. This vulnerability arises from improper neutralization of user-supplied input during web page generation, classified under CWE-79. When a user interacts with the affected functionality, malicious scripts embedded in crafted URLs or inputs can be executed in the victim's browser context. This reflected XSS does not require authentication or privileges, making it accessible to unauthenticated remote attackers. The vulnerability affects versions prior to 3.7.7 of the CHS product. The CVSS 4.0 vector indicates network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), but requires user interaction (UI:A). The impact does not affect confidentiality, integrity, or availability directly but can lead to indirect consequences such as session hijacking, credential theft, or unauthorized actions performed via the victim's browser session. No known public exploits exist yet, but the vulnerability is publicly disclosed and should be addressed promptly. The lack of a patch link suggests that a fix may be pending or users need to upgrade to version 3.7.7 or later where the issue is resolved.

For European organizations, especially those in industrial automation, manufacturing, and critical infrastructure sectors using the CONPROSYS HMI System, this vulnerability poses a risk of client-side script execution leading to session hijacking, phishing, or unauthorized control actions within the HMI interface. Such impacts could disrupt operational technology (OT) environments, potentially causing safety risks or production downtime. Although the vulnerability does not directly compromise system confidentiality, integrity, or availability, the indirect effects of successful XSS attacks can undermine trust in the HMI system and lead to broader security incidents. The requirement for user interaction limits mass exploitation but targeted spear-phishing or social engineering attacks could be effective. The absence of known exploits currently reduces immediate risk but does not eliminate the threat, especially as attackers often weaponize disclosed vulnerabilities over time.

1. Upgrade the CONPROSYS HMI System to version 3.7.7 or later where the vulnerability is fixed. 2. If immediate upgrade is not possible, implement web application firewall (WAF) rules to detect and block malicious input patterns targeting getqsetting.php. 3. Employ strict input validation and output encoding on all user-controllable inputs within the HMI web interface to prevent script injection. 4. Educate users and operators about the risks of clicking on suspicious links or interacting with untrusted content related to the HMI system. 5. Monitor web server logs for unusual requests to getqsetting.php that may indicate attempted exploitation. 6. Segment the HMI system network to limit exposure to external networks and reduce attack surface. 7. Implement Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers accessing the HMI system. 8. Regularly audit and update all industrial control system components to maintain security hygiene.