CVE-2025-66101 identifies a missing authorization vulnerability in the Sabuj Kundu CBX Bookmark & Favorite WordPress plugin, specifically affecting versions up to and including 2.0.1. The vulnerability arises from incorrectly configured access control security levels, which fail to properly enforce authorization checks on certain plugin functionalities. This misconfiguration allows an attacker to bypass intended access restrictions, potentially enabling unauthorized users to perform actions such as viewing, modifying, or deleting bookmarks and favorites managed by the plugin. The issue is classified as an access control vulnerability, which is critical in maintaining the confidentiality and integrity of user data within WordPress environments. No CVSS score has been assigned yet, and there are no known exploits in the wild, indicating that exploitation may require some technical knowledge or specific conditions. However, the plugin’s role in managing user-specific data means that exploitation could lead to unauthorized data exposure or manipulation, impacting user trust and system security. The vulnerability was published on November 21, 2025, and is tracked under the CVE identifier CVE-2025-66101. The absence of patches at the time of publication necessitates immediate attention to access control policies and monitoring for suspicious activity related to the plugin. Given that WordPress is widely used across Europe, and this plugin may be deployed in various organizational websites, the vulnerability represents a tangible risk to affected installations.

For European organizations, the missing authorization vulnerability in the CBX Bookmark & Favorite plugin could lead to unauthorized access to user-specific data such as bookmarks and favorites, potentially resulting in data leakage or unauthorized data manipulation. This can undermine user privacy and trust, especially for organizations handling sensitive or proprietary information. The integrity of user data may be compromised if attackers modify or delete bookmarks, which could disrupt business workflows or user experience. Although the vulnerability does not directly affect system availability, the indirect consequences of data tampering or exposure could lead to reputational damage and compliance issues under regulations like GDPR. Organizations relying on WordPress for customer engagement, content management, or internal collaboration are particularly at risk. The lack of known exploits currently reduces immediate threat levels but does not eliminate the risk of future exploitation. European entities with limited patch management resources or those using outdated plugin versions are more vulnerable. Additionally, the vulnerability could be leveraged as a foothold for further attacks if combined with other weaknesses in the environment.

1. Immediately audit all WordPress installations for the presence of the Sabuj Kundu CBX Bookmark & Favorite plugin and identify versions up to 2.0.1. 2. Restrict plugin usage to trusted users with minimal necessary privileges to reduce the attack surface. 3. Implement strict access control policies at the WordPress level, ensuring that only authorized users can access or modify bookmark-related functionalities. 4. Monitor logs and user activity for unusual access patterns or unauthorized attempts to interact with the plugin. 5. Engage with the plugin vendor or community to obtain and apply security patches as soon as they become available. 6. Consider disabling or uninstalling the plugin temporarily if it is not essential to operations until a secure version is released. 7. Educate administrators and developers about the risks of misconfigured access controls and the importance of regular plugin updates. 8. Employ web application firewalls (WAF) with custom rules to detect and block suspicious requests targeting the plugin endpoints. 9. Conduct penetration testing focused on access control mechanisms within WordPress environments to identify similar vulnerabilities proactively.