The Login Lockdown & Protection plugin for WordPress is vulnerable to unauthorized nonce access due to a missing capability check on the ajax_run_tool function in all versions up to, and including, 2.11. This makes it possible for authenticated attackers, with Subscriber-level access and above, to obtain a valid nonce that can be used to generate a global unlock key, which can in turn be used to add arbitrary IP address to the plugin allowlist. This can only by exploited on new installations where the site administrator hasn't visited the loginlockdown page yet.
https://plugins.trac.wordpress.org/changeset/3286814/login-lockdown
https://plugins.trac.wordpress.org/browser/login-lockdown/trunk/libs/ajax.php#L17