CVE-2025-5919 is a vulnerability classified under CWE-862 (Missing Authorization) found in the WP Timetics Appointment Booking Calendar plugin for WordPress, developed by arraytics. The issue arises because the plugin's update and register_routes functions lack proper capability checks, allowing unauthenticated users to access and modify booking data. This means that any attacker can interact with the plugin's API endpoints or routes to retrieve sensitive booking information or alter bookings without needing to log in or have any privileges. The vulnerability affects all versions up to and including 1.0.36, with no patches currently available. The CVSS 3.1 base score is 6.5, indicating medium severity, with attack vector network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), and impact limited to confidentiality and integrity (C:L/I:L/A:N). This vulnerability could lead to unauthorized disclosure of personal or business-sensitive booking data and manipulation of appointments, potentially disrupting business operations or violating privacy regulations. No known exploits have been reported in the wild yet, but the ease of exploitation and lack of authentication requirements make it a significant risk for affected WordPress sites. The plugin is commonly used by businesses to manage appointment scheduling, making it a valuable target for attackers aiming to disrupt services or steal data.

For European organizations, this vulnerability poses a risk primarily to confidentiality and integrity of booking data managed through the WP Timetics plugin. Unauthorized access could lead to exposure of personal customer information, appointment details, and potentially sensitive business data. Modification of bookings could disrupt service delivery, cause reputational damage, and lead to customer dissatisfaction. Organizations in sectors such as healthcare, legal, education, and personal services that rely on online appointment scheduling are particularly vulnerable. Additionally, exposure of personal data could result in violations of GDPR, leading to regulatory penalties and legal consequences. While availability is not directly impacted, the indirect effects of data manipulation could cause operational disruptions. The lack of authentication requirements and ease of exploitation increase the likelihood of attacks, especially on publicly accessible WordPress sites. Given the widespread use of WordPress in Europe, the potential attack surface is significant, necessitating urgent attention to mitigation.

1. Immediately audit all WordPress sites using the WP Timetics Appointment Booking Calendar plugin to identify affected versions (up to 1.0.36). 2. Restrict access to the plugin’s API endpoints and routes via web application firewall (WAF) rules or server-level access controls to block unauthenticated requests. 3. Implement strict IP whitelisting or VPN access for administrative and booking management interfaces where feasible. 4. Monitor web server and application logs for unusual or unauthorized access patterns targeting the plugin’s routes. 5. Disable or remove the plugin temporarily if it is not critical to operations until an official patch is released. 6. Subscribe to vendor and security mailing lists to receive timely updates and apply patches immediately once available. 7. Conduct regular security assessments and penetration tests focusing on WordPress plugins and their authorization mechanisms. 8. Educate site administrators on the risks of unauthorized access and the importance of plugin updates and security hygiene. 9. Consider alternative booking plugins with stronger security track records if immediate patching is not possible. 10. Ensure backups of booking data are maintained securely to enable recovery in case of data tampering.