The 6Storage Rentals plugin for WordPress is vulnerable to Authorization Bypass Through User-Controlled Key in all versions up to and including 2.22.0 via the userId parameter of the six_storage_get_user_info and six_storage_update_profile AJAX actions. This is due to the six_storage_getUserInfo() and six_storage_updateProfile() functions being registered on wp_ajax_nopriv_* hooks and accepting a tenant identifier directly from $_POST['userId'] without performing any ownership verification, session binding, or nonce validation to confirm the requester has a legitimate relationship to the supplied ID. This makes it possible for unauthenticated attackers to read and modify arbitrary tenants' profile data — including name, email address, phone number, physical address, and SSN — by supplying an enumerated userId value in a crafted request to either handler.