CVE-2025-15043: Events Calendar Auth Bypass Vulnerability

CVE-2025-15043 Overview

The Events Calendar plugin for WordPress contains an authorization bypass vulnerability due to missing capability checks on critical database migration functions. Specifically, the start_migration, cancel_migration, and revert_migration functions in all versions up to and including 6.15.13 fail to verify user permissions before executing sensitive operations. This flaw allows authenticated attackers with subscriber-level access or above to manipulate the Custom Tables V1 database migration process, including the ability to completely drop custom database tables via the revert action.

Critical Impact

Authenticated attackers with minimal subscriber privileges can manipulate database migrations, potentially dropping custom database tables and causing significant data loss or service disruption for WordPress sites using The Events Calendar plugin.

Affected Products

• The Events Calendar WordPress Plugin versions up to and including 6.15.13
• WordPress installations with The Events Calendar plugin active
• Sites utilizing Custom Tables V1 database migration feature

Discovery Timeline

• 2026-01-20 - CVE CVE-2025-15043 published to NVD
• 2026-01-20 - Last updated in NVD database

Technical Details for CVE-2025-15043

Vulnerability Analysis

This vulnerability is classified under CWE-862 (Missing Authorization), representing a broken access control flaw in the plugin's migration management functionality. The vulnerability exists because the affected functions do not implement proper capability checks before performing privileged database operations.

In WordPress, plugins should verify user capabilities using functions like current_user_can() before allowing access to administrative features. The Events Calendar plugin failed to implement these checks on the migration-related endpoints, creating a privilege escalation pathway that allows low-privileged users to execute actions intended only for administrators.

The attack requires network access and authentication with at least subscriber-level privileges. While this limits the attack surface to authenticated users, subscriber accounts are commonly available on WordPress sites with open registration, making this vulnerability practically exploitable in many deployment scenarios.

Root Cause

The root cause is the absence of capability verification in the start_migration, cancel_migration, and revert_migration functions. These functions handle sensitive database schema operations for the Custom Tables V1 migration feature but execute without confirming that the requesting user has administrator-level privileges. This missing authorization check allows any authenticated user, regardless of their role, to invoke these privileged operations.

Attack Vector

An attacker with subscriber-level credentials can craft requests to the vulnerable migration endpoints. The most severe attack path involves triggering the revert_migration function, which drops custom database tables entirely. This could result in:

1. Complete loss of event data stored in custom tables
2. Service disruption for sites relying on The Events Calendar functionality
3. Potential cascading failures if other plugins or themes depend on this data

The attack is network-based and requires only low-level authentication, with no user interaction needed. The attacker sends authenticated requests to the migration function endpoints, bypassing the intended administrative controls. Since the functions lack proper authorization checks, the WordPress core accepts the requests from any authenticated session.

Detection Methods for CVE-2025-15043

Indicators of Compromise

• Unexpected database table modifications or deletions related to The Events Calendar custom tables
• Audit log entries showing migration actions initiated by non-administrator users
• Subscriber or contributor-level accounts making requests to migration endpoints
• Sudden loss of event data or calendar functionality without administrative changes

Detection Strategies

• Monitor WordPress audit logs for unauthorized access to migration-related AJAX actions
• Implement web application firewall rules to detect requests to migration endpoints from non-admin user sessions
• Review access logs for patterns of authenticated requests targeting The Events Calendar admin functions
• Deploy file integrity monitoring to detect unauthorized plugin modifications

Monitoring Recommendations

• Enable comprehensive WordPress activity logging covering plugin administrative actions
• Set up alerts for database schema changes, particularly table drops or migrations
• Monitor user role assignments for unusual privilege patterns
• Implement real-time alerting for subscriber-level accounts accessing administrative endpoints

How to Mitigate CVE-2025-15043

Immediate Actions Required

• Update The Events Calendar plugin to version 6.15.13.1 or later immediately
• Audit recent migration activity and database changes for signs of exploitation
• Review user accounts with subscriber-level access for suspicious activity
• Temporarily disable open user registration if patching cannot be performed immediately

Patch Information

The vendor has released version 6.15.13.1 which addresses this vulnerability by implementing proper capability checks on the affected migration functions. The patch can be reviewed in the WordPress Plugin Changeset. Additional technical details are available in the Wordfence Vulnerability Report.

Workarounds

• Restrict subscriber and contributor account registration until the patch can be applied
• Implement web application firewall rules to block requests to migration endpoints from non-administrator users
• Use a WordPress security plugin to enforce stricter capability requirements on plugin administrative functions
• Back up the database regularly to enable recovery if tables are maliciously dropped