CVE-2025-6676 is a Cross-Site Scripting (XSS) vulnerability classified under CWE-79, affecting the Drupal Simple XML sitemap module versions from 0.0.0 up to but not including 4.2.2. This vulnerability arises due to improper neutralization of input during web page generation, allowing malicious actors to inject arbitrary scripts into web pages generated by the vulnerable module. The Simple XML sitemap module is used to generate XML sitemaps that help search engines index website content. The vulnerability occurs because user-supplied input is not properly sanitized or encoded before being included in the sitemap output, which can be rendered in web browsers or other clients that process the sitemap. Exploiting this vulnerability could allow attackers to execute arbitrary JavaScript in the context of the victim's browser, potentially leading to session hijacking, defacement, redirection to malicious sites, or other malicious actions. Although no known exploits are reported in the wild yet, the vulnerability is publicly disclosed and unpatched in versions prior to 4.2.2, making it a credible risk for sites using affected versions. The lack of a CVSS score indicates that the severity has not been formally assessed, but the nature of XSS vulnerabilities generally implies a significant risk, especially for websites with authenticated users or sensitive data. The vulnerability is specific to the Simple XML sitemap module within Drupal, a widely used content management system, which increases the potential attack surface given Drupal's popularity in Europe and globally.

For European organizations, this vulnerability poses several risks. Many European public sector websites, educational institutions, and enterprises use Drupal for their web presence, often relying on modules like Simple XML sitemap for SEO and indexing purposes. Successful exploitation could lead to compromise of user sessions, unauthorized actions on behalf of users, theft of sensitive information, or distribution of malware through injected scripts. This is particularly concerning for organizations subject to GDPR, as data breaches involving personal data could lead to regulatory penalties and reputational damage. Additionally, the vulnerability could be leveraged in targeted attacks against high-profile entities or critical infrastructure operators that use Drupal, potentially disrupting services or undermining trust in digital services. The impact extends beyond confidentiality to integrity and availability, as attackers could manipulate website content or cause denial of service through malicious payloads. Given the widespread use of Drupal in Europe, the threat could affect a broad range of sectors including government, finance, healthcare, and media.

Organizations should immediately verify if they use the Simple XML sitemap module in Drupal and identify the version in use. Upgrading to version 4.2.2 or later, where the vulnerability is fixed, is the primary and most effective mitigation. If immediate upgrade is not feasible, organizations should implement strict input validation and output encoding on any user-supplied data that could be included in sitemap generation. Web application firewalls (WAFs) can be configured to detect and block common XSS payloads targeting sitemap URLs. Additionally, security teams should monitor web logs for suspicious requests and unusual sitemap content changes. Employing Content Security Policy (CSP) headers can help mitigate the impact of XSS by restricting script execution contexts. Regular security audits and penetration testing focusing on XSS vulnerabilities in Drupal modules are recommended. Finally, educating developers and administrators about secure coding practices and timely patch management is critical to prevent exploitation.