Ticket #22516: 22516.diff

wp-includes/user.php

@@ -70 +70 @@
  */
 add_filter('authenticate', 'wp_authenticate_username_password', 20, 3);
 function wp_authenticate_username_password($user, $username, $password) {
+        if ( is_wp_error( $user ) ) { return $user; }
         if ( is_a($user, 'WP_User') ) { return $user; }
 
         if ( empty($username) || empty($password) ) {