CVE-2025-10018 is a stored Cross-Site Scripting (XSS) vulnerability classified under CWE-79 affecting OpenSolution QuickCMS version 6.8. The flaw resides in the language editor functionality, which allows an attacker with administrative privileges to inject arbitrary HTML and JavaScript code into the website's pages. This malicious code is stored persistently and executed whenever any user accesses affected pages, potentially leading to session hijacking, defacement, or further exploitation. Although the default admin user interface restricts direct JavaScript insertion, the vulnerability enables bypassing these controls through the language editor's input handling. The vendor was notified early but has not disclosed detailed vulnerability information or released patches, and other versions beyond 6.8 have not been tested but may also be vulnerable. The CVSS 4.0 vector indicates network attack vector, low attack complexity, no privileges required beyond admin, and user interaction is necessary for the malicious payload to execute. No known exploits have been reported in the wild. The vulnerability's persistence and ability to affect all website visitors make it a significant risk for organizations relying on QuickCMS for content management, especially where multiple administrators have access to the language editor. The lack of vendor response and patch availability increases the urgency for organizations to implement compensating controls.

For European organizations, this vulnerability poses a risk primarily to websites managed with QuickCMS version 6.8, especially those with multiple administrators who could be compromised or act maliciously. Successful exploitation can lead to persistent XSS attacks, enabling attackers to steal session cookies, perform unauthorized actions on behalf of users, deface websites, or distribute malware to visitors. This can damage organizational reputation, lead to data breaches, and violate data protection regulations such as GDPR if personal data is compromised. Public-facing websites of government, educational institutions, or businesses using QuickCMS are particularly at risk. The medium CVSS score reflects that exploitation requires admin privileges and some user interaction, limiting the attack scope but not eliminating risk. The absence of patches and vendor communication increases exposure time, potentially inviting targeted attacks. Additionally, the vulnerability could be leveraged as part of a broader attack chain, especially in environments where QuickCMS is integrated with other systems.

1. Restrict administrative access to QuickCMS, ensuring only trusted and trained personnel have admin privileges, particularly access to the language editor. 2. Implement strict input validation and sanitization on all language editor inputs, either by applying custom filters or using web application firewalls (WAF) to detect and block malicious payloads. 3. Monitor website content regularly for unauthorized or suspicious HTML/JavaScript injections. 4. Isolate QuickCMS administrative interfaces behind VPNs or IP whitelisting to reduce exposure. 5. Educate administrators about the risks of injecting untrusted content and the importance of secure content management practices. 6. Maintain regular backups of website content to enable quick restoration if defacement occurs. 7. Stay alert for vendor updates or patches and apply them immediately once available. 8. Consider migrating to alternative CMS platforms if QuickCMS support remains unresponsive. 9. Employ Content Security Policy (CSP) headers to limit the execution of unauthorized scripts on the website. 10. Conduct periodic security audits and penetration tests focusing on CMS components.