CVE-2025-52669 is a vulnerability identified in the Revive Adserver software, specifically affecting versions 5.5.2, 6.0.1, and earlier. The root cause lies in insecure design policies within the user management system, which inadvertently grant non-administrative users access to sensitive personal information of other users, namely contact names and email addresses. This issue is classified under CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor). The vulnerability does not require user interaction and can be exploited remotely over the network with low privileges (non-admin user account). The CVSS v3.0 base score is 4.3, indicating a medium severity level, primarily due to the confidentiality impact without affecting integrity or availability. Although no public exploits are currently known, the exposure of user contact information can facilitate targeted phishing, social engineering, or further reconnaissance attacks. The lack of patches at the time of publication means organizations must rely on compensating controls. The vulnerability affects the confidentiality of user data but does not compromise system functionality or data integrity. Given Revive Adserver’s role in managing digital advertising campaigns, unauthorized access to user contact details could also lead to reputational damage and regulatory compliance issues, especially under GDPR in Europe.

For European organizations, the primary impact is the unauthorized disclosure of user contact information, which can lead to privacy violations and increased risk of phishing or spear-phishing attacks targeting employees or partners. This exposure may also result in non-compliance with GDPR requirements concerning personal data protection, potentially leading to legal penalties and reputational harm. Since Revive Adserver is widely used by digital marketing agencies and publishers across Europe, the vulnerability could affect a broad range of organizations involved in online advertising. While the vulnerability does not directly compromise system integrity or availability, the indirect consequences of data leakage and subsequent social engineering attacks could disrupt business operations and erode trust with clients and users. Organizations handling sensitive or large volumes of user data are particularly at risk. The absence of known exploits reduces immediate threat but does not eliminate the risk of future exploitation.

Until official patches are released, European organizations should implement strict access control policies to limit user permissions within Revive Adserver, ensuring that only trusted users have accounts and that non-admin users have minimal privileges. Conduct thorough audits of user roles and remove or disable unnecessary accounts. Monitor system and access logs for unusual activity indicative of data scraping or unauthorized access attempts. Employ network segmentation to restrict access to the ad server to trusted internal networks or VPNs. Consider implementing additional application-layer protections such as web application firewalls (WAFs) to detect and block suspicious requests targeting user management endpoints. Educate users about phishing risks and encourage vigilance against suspicious emails that could leverage leaked contact information. Once patches become available, prioritize timely deployment. Additionally, review and update privacy policies and incident response plans to address potential data exposure scenarios.