A single-function plugin to stop usernames enumeration

stop-wordpress-user-phishing.php

<?php

/**
 * Plugin Name: Stop Username Phishing
 * Plugin URI: https://gist.github.com/alexmoise/d5d9073e6165d4e5ac098a184d5405e6
 * Description: A single-function plugin to stop usernames enumeration using author ID
 * Version: 1.0
 * Author: Alex Moise
 * Author URI: https://moise.pro
 */
 
// just block user enumeration using author ID
if (!is_admin()) { if (preg_match('/author=([0-9]*)/i', $_SERVER['QUERY_STRING'])) die();
	add_filter('redirect_canonical', 'mo_block_user_enumeration', 10, 2);
}
function mo_block_user_enumeration($redirect, $request) {
	if (preg_match('/\?author=([0-9]*)(\/*)/i', $request)) die();
	else return $redirect;
}

?>