CVE-2025-31675 is a Cross-Site Scripting (XSS) vulnerability identified in the Drupal core content management system, affecting multiple major versions including 8.0.0 through versions prior to 10.3.14, 10.4.0 through versions prior to 10.4.5, 11.0.0 through versions prior to 11.0.13, and 11.1.0 through versions prior to 11.1.5. The vulnerability arises from improper neutralization of input during web page generation, classified under CWE-79, which allows an attacker to inject malicious scripts into web pages viewed by other users. The vulnerability requires network access (AV:N), low attack complexity (AC:L), and privileges (PR:L) but does require user interaction (UI:R) to trigger the exploit. The scope is changed (S:C), indicating that the vulnerability can affect resources beyond the initially vulnerable component. The impact includes limited confidentiality and integrity loss (C:L, I:L) but no impact on availability (A:N). This means an attacker could potentially steal or manipulate data accessible to the user or perform actions on their behalf but cannot disrupt service availability. No known exploits are currently reported in the wild. The vulnerability affects Drupal core, a widely used open-source CMS platform powering numerous websites globally, including many European organizations. The lack of patch links suggests that fixes are either newly released or pending, emphasizing the need for timely updates. Given the medium CVSS score of 5.4, this vulnerability represents a moderate risk that could be leveraged in targeted attacks, especially in environments where users have elevated privileges or sensitive data is handled.

For European organizations, the impact of CVE-2025-31675 can be significant due to Drupal's widespread adoption in government portals, educational institutions, and private sector websites. Successful exploitation could lead to unauthorized disclosure of sensitive user information, session hijacking, or unauthorized actions performed on behalf of legitimate users. This can undermine user trust, lead to data breaches under GDPR regulations, and cause reputational damage. The vulnerability's requirement for user interaction means phishing or social engineering could be used to lure users into triggering the exploit. The changed scope indicates that the attack could affect multiple components or user roles, potentially escalating the impact. Organizations relying on Drupal for public-facing services or internal portals should be particularly cautious, as attackers might exploit this vulnerability to gain footholds or pivot within networks. Although no active exploits are known, the medium severity and ease of exploitation (low complexity) necessitate proactive mitigation to prevent future attacks.

1. Immediate application of official Drupal core updates to versions 10.3.14, 10.4.5, 11.0.13, or 11.1.5 and later is critical to remediate the vulnerability. 2. Conduct a thorough audit of all Drupal instances to identify affected versions and prioritize patching accordingly. 3. Implement strict Content Security Policy (CSP) headers to reduce the risk of script injection exploitation by restricting the sources of executable scripts. 4. Review and sanitize all user-generated content inputs beyond Drupal's default mechanisms, especially in custom modules or themes, to ensure no unescaped input is rendered. 5. Enhance user awareness training focused on phishing and social engineering tactics that could trigger user interaction-based exploits. 6. Monitor web server and application logs for unusual script injection attempts or anomalous user behavior indicative of exploitation attempts. 7. Employ Web Application Firewalls (WAFs) with updated Drupal-specific rules to detect and block XSS attack patterns. 8. Limit user privileges where possible to reduce the impact of compromised accounts, especially for users with elevated permissions. 9. For organizations with multiple Drupal deployments, automate patch management and vulnerability scanning to maintain consistent security posture.