CVE-2025-15043 is a vulnerability classified under CWE-862 (Missing Authorization) affecting The Events Calendar plugin for WordPress, developed by stellarwp. The vulnerability arises because the plugin fails to perform proper capability checks on three critical functions related to database migration: 'start_migration', 'cancel_migration', and 'revert_migration'. These functions manage the Custom Tables V1 migration process, which involves creating, modifying, or dropping custom database tables used by the plugin. The absence of authorization checks means that any authenticated user with at least subscriber-level privileges can invoke these functions. This unauthorized access enables attackers to start or cancel migrations arbitrarily or revert migrations, which can result in dropping custom tables, leading to data loss and service disruption. The vulnerability affects all versions up to and including 6.15.13. The CVSS 3.1 base score is 5.4, indicating medium severity, with an attack vector of network (remote exploitation), low attack complexity, privileges required at the level of authenticated users with subscriber or higher roles, no user interaction needed, and impacts limited to integrity and availability without confidentiality loss. No patches or exploit code are currently publicly available, and no known exploits in the wild have been reported. The flaw is significant because WordPress powers a large portion of websites globally, and The Events Calendar is a widely used plugin for event management. Unauthorized manipulation of database migrations can cause downtime, data loss, and require recovery efforts, impacting website reliability and trustworthiness.

For European organizations, the impact of this vulnerability can be substantial, especially for those relying on The Events Calendar plugin for critical event management on their WordPress sites. The ability for low-privileged authenticated users to manipulate database migrations can lead to accidental or malicious data loss by dropping custom tables, causing service outages and loss of event data integrity. This can disrupt business operations, damage reputation, and incur recovery costs. Organizations in sectors such as event management, education, cultural institutions, and public services that use this plugin are particularly at risk. The disruption of event data can affect customer engagement, scheduling, and communication. Additionally, the integrity compromise may undermine trust in the organization's digital services. Since the vulnerability requires only subscriber-level access, attackers could exploit compromised or weak user accounts, increasing the attack surface. The medium CVSS score reflects moderate risk, but the real-world impact depends on the deployment context and user role management practices.

European organizations should implement the following specific mitigations: 1) Immediately audit user roles and permissions on WordPress sites using The Events Calendar, ensuring that subscriber-level accounts are tightly controlled and monitored. 2) Restrict subscriber accounts from accessing or invoking migration-related functions by applying custom capability filters or role restrictions via WordPress hooks or security plugins. 3) Monitor logs for any unusual activity related to database migrations or plugin function calls, setting alerts for migration start, cancel, or revert actions. 4) Backup the WordPress database regularly, with special attention to custom tables used by The Events Calendar, enabling rapid recovery if tables are dropped. 5) Stay informed about official patches or updates from stellarwp and apply them promptly once released. 6) Consider temporarily disabling migration features or the plugin if migration functionality is not needed, reducing the attack surface. 7) Employ Web Application Firewalls (WAFs) with rules to detect and block unauthorized attempts to invoke migration endpoints. 8) Educate site administrators and users about the risks of privilege escalation and enforce strong authentication mechanisms to prevent account compromise.