Ticket #22858: 22858.patch

wp-includes/user.php

@@ -1452 +1452 @@
 
         // First, get all of the original fields
         $user_obj = get_userdata( $ID );
+        if ( ! $user_obj )
+                return new WP_Error( 'invalid_user_id', __( 'Invalid user ID.' ) );
 
         $user = $user_obj->to_array();