CVE-2025-12412 is a Cross-Site Request Forgery (CSRF) vulnerability identified in the Top Bar Notification plugin for WordPress, maintained by josereyev. This vulnerability exists in all versions up to and including 1.12 due to missing or incorrect nonce validation in the tbn_ajax_add() function, which handles AJAX requests for adding notifications. Nonce validation is a security mechanism designed to ensure that requests are legitimate and initiated by authorized users. The absence or improper implementation of this validation allows an attacker to craft a malicious request that, when executed by an authenticated administrator (via social engineering such as clicking a link), can modify plugin settings and inject malicious web scripts. This can lead to unauthorized changes in the plugin's behavior, potentially enabling further attacks like persistent cross-site scripting (XSS) or site defacement. The vulnerability does not require the attacker to be authenticated but does require user interaction from an administrator, increasing the attack complexity. The CVSS v3.1 score of 6.1 reflects a medium severity, with an attack vector of network (remote), low attack complexity, no privileges required, but requiring user interaction. The scope is changed, indicating that the vulnerability affects components beyond the initially vulnerable code, potentially impacting the broader WordPress site. No patches or known exploits have been reported at the time of publication, but the risk remains significant due to the widespread use of WordPress and its plugins. The vulnerability is classified under CWE-352, which covers CSRF issues where unauthorized commands are transmitted from a user that the web application trusts.

For European organizations, the impact of this vulnerability can be considerable, especially for those relying on WordPress websites for business operations, customer engagement, or internal communications. Successful exploitation could allow attackers to alter plugin settings and inject malicious scripts, potentially leading to data leakage, defacement, or further compromise of the website and its users. This undermines confidentiality and integrity of the affected systems and can damage organizational reputation and trust. Since the vulnerability requires tricking an administrator, organizations with less security awareness or inadequate training are at higher risk. The lack of availability impact means service disruption is unlikely, but the integrity and confidentiality risks can lead to regulatory compliance issues under GDPR if personal data is exposed or manipulated. Given the popularity of WordPress in Europe, especially among SMEs and public sector entities, the threat is relevant and should be addressed promptly to avoid exploitation.

Organizations should immediately verify if they use the Top Bar Notification plugin version 1.12 or earlier on their WordPress sites. Although no official patch is currently available, administrators should monitor the vendor's channels for updates and apply patches as soon as they are released. In the interim, consider disabling or uninstalling the plugin if it is not critical. Implement strict nonce validation for AJAX requests in custom or third-party plugins to prevent similar CSRF issues. Enhance administrator security awareness training to recognize phishing and social engineering attempts that could lead to clicking malicious links. Employ Content Security Policy (CSP) headers to mitigate the impact of injected scripts. Limit administrative access to trusted networks or use multi-factor authentication to reduce the risk of compromised credentials facilitating exploitation. Regularly audit WordPress plugins and themes for vulnerabilities and maintain an up-to-date inventory to quickly respond to new threats.