The PeproDev Ultimate Profile Solutions plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the handel_ajax_req() function in versions 1.9.1 to 7.5.2. This makes it possible for unauthenticated attackers to update arbitrary user's metadata which can be leveraged to block an administrator from accessing their site when wp_capabilities is set to 0.
https://wordpress.org/plugins/peprodev-ups/#developers
https://plugins.trac.wordpress.org/browser/peprodev-ups/tags/7.5.2/login/login.php#L1483