CVE-2025-15466 is a vulnerability classified under CWE-862 (Missing Authorization) found in the 'Image Photo Gallery Final Tiles Grid' WordPress plugin developed by wpchill. This plugin, widely used for managing photo galleries in WordPress sites, suffers from a lack of proper capability checks on several AJAX endpoints. These endpoints handle critical gallery management functions such as viewing, creating, modifying, cloning, deleting, and reassigning ownership of galleries. The vulnerability affects all versions up to and including 3.6.9. An attacker with authenticated access at the Contributor role or higher can exploit this flaw to manipulate galleries created by other users, including administrators, without proper authorization. The attack vector is network-based and does not require user interaction, increasing the ease of exploitation. The CVSS v3.1 base score is 5.4 (medium severity), reflecting low complexity and low privileges required but limited impact on availability. The vulnerability compromises confidentiality and integrity by enabling unauthorized data access and modification. No patches are currently available, and no known exploits have been reported in the wild. The issue was publicly disclosed in January 2026 by Wordfence, with the vulnerability reserved earlier that month. Organizations using this plugin in multi-user WordPress environments are at risk of privilege escalation and unauthorized data manipulation.

For European organizations, this vulnerability poses a significant risk to the confidentiality and integrity of digital assets managed via WordPress sites using the affected plugin. Unauthorized users with Contributor-level access can escalate privileges to manipulate galleries owned by other users, potentially including sensitive or proprietary images. This could lead to data leakage, unauthorized content modification, or disruption of digital asset management workflows. While availability is not directly impacted, the trustworthiness and integrity of content are compromised, which can affect brand reputation and compliance with data protection regulations such as GDPR. Organizations with collaborative content management environments, such as media companies, marketing agencies, and educational institutions, are particularly vulnerable. The lack of a patch increases exposure time, and the ease of exploitation means attackers can leverage this vulnerability to gain unauthorized control over gallery content without requiring administrator credentials or user interaction.

Immediate mitigation should focus on restricting Contributor-level access and above to trusted users only, minimizing the number of users who can exploit this vulnerability. Administrators should audit user roles and permissions to ensure no unnecessary privileges are granted. Until an official patch is released, consider disabling or removing the 'Image Photo Gallery Final Tiles Grid' plugin if feasible, especially in high-risk environments. Implement web application firewalls (WAFs) with custom rules to monitor and block suspicious AJAX requests targeting gallery management endpoints. Regularly monitor WordPress and plugin update channels for the release of a security patch and apply it promptly. Additionally, enable detailed logging of user actions related to gallery management to detect potential exploitation attempts. Educate site administrators and content managers about the risks associated with this vulnerability and encourage the use of strong authentication methods to reduce the risk of compromised accounts.