The Eventin – Event Calendar, Tickets, Registration, Booking & WooCommerce plugin for WordPress...

The Eventin – Event Calendar, Tickets, Registration, Booking & WooCommerce plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 4.1.23. This is due to the PermissionManager::manage_permissions() function being registered as a callback on WordPress core's map_meta_cap filter and unconditionally returning the always-true 'exist' primitive for every capability check whenever the evaluated user ID is 1, without scoping this behavior to plugin-specific capabilities. This makes it possible for authenticated attackers whose account is user ID 1, even subscribers, to pass every WordPress capability check, including manage_options, edit_plugins, edit_themes, promote_users, and update_core, thereby elevating their privileges to administrator-equivalent power and achieving full site takeover, including remote code execution via the plugin and theme editors. Exploitation is only impactful when user ID 1 has been deliberately demoted to a lower-privilege role as a common administrator-account hardening practice; on default installations where user ID 1 retains the administrator role, no incremental privilege gain occurs.