CVE-2025-12366 is an authorization bypass vulnerability classified under CWE-639 (Authorization Bypass Through User-Controlled Key) affecting the Page Builder: Pagelayer – Drag and Drop website builder plugin for WordPress, developed by softaculous. The vulnerability exists in all versions up to and including 2.0.5 within the pagelayer_replace_page function. This function fails to properly validate a user-controlled key parameter, resulting in an insecure direct object reference (IDOR). Consequently, authenticated attackers with Author-level privileges or higher can exploit this flaw to replace media files owned by other users, including administrators. This unauthorized modification capability undermines the integrity of website content and media assets. The vulnerability is remotely exploitable over the network without requiring user interaction, but it does require the attacker to have at least Author-level access, which is a moderate privilege level in WordPress. The CVSS v3.1 base score is 4.3, reflecting a medium severity primarily due to the limited impact on confidentiality and availability, but notable integrity impact. No patches or known exploits are currently reported, indicating the need for proactive mitigation. The vulnerability is significant for websites relying on this plugin, as unauthorized media replacement can lead to defacement, misinformation, or embedding malicious content. The flaw highlights the importance of robust access control and input validation in WordPress plugins handling user-supplied keys or identifiers.

For European organizations, the impact of CVE-2025-12366 primarily concerns the integrity of web content hosted on WordPress sites using the vulnerable Page Builder: Pagelayer plugin. Attackers with Author-level access can replace media files belonging to other users, including administrators, potentially leading to website defacement, misinformation, or injection of malicious media content. This can damage brand reputation, erode customer trust, and potentially facilitate further attacks such as phishing or malware distribution. Although the vulnerability does not directly compromise confidentiality or availability, the unauthorized modification of media assets can disrupt business operations and require costly remediation efforts. Organizations in sectors with high reliance on web presence, such as e-commerce, media, and public services, may face increased risk. Additionally, regulatory compliance under GDPR may be implicated if the integrity breach leads to exposure or misuse of personal data embedded in media files. The requirement for authenticated access limits the attack surface but does not eliminate risk, especially in environments with multiple content contributors or compromised user credentials.

To mitigate CVE-2025-12366, organizations should first verify if their WordPress installations use the Page Builder: Pagelayer plugin and identify the version in use. Immediate steps include restricting Author-level permissions to trusted users only and auditing existing user roles to minimize unnecessary elevated privileges. Since no official patch is currently available, consider disabling or uninstalling the plugin temporarily to prevent exploitation. Implement strict monitoring and logging of media file changes to detect unauthorized modifications promptly. Employ web application firewalls (WAFs) with custom rules to detect and block suspicious requests targeting the pagelayer_replace_page function or related endpoints. Regularly update WordPress core and plugins to the latest versions once a patch is released. Additionally, conduct periodic security reviews of user access controls and enforce strong authentication mechanisms, such as multi-factor authentication (MFA), to reduce the risk of compromised accounts. For organizations with development capabilities, reviewing and hardening the plugin’s source code or applying custom validation on user-controlled keys can serve as an interim protective measure.