How to set up a redirect to 404 pages like site.eu/?hmb=654654?

Question

WordPress

Friends, I made a new site for the guys, when I connected Yandex.Webmaster and Metrica, I found out that in the search there are pages like site.ru/?hmb=Zapros-poiska
There were no such pages, so I suggested that the previous site was infected and the links were just redirected somewhere. Well, not the point.
Now the site is new, but these pages are in the search, and accordingly spoil all the statistics. I found in Yandex help how to remove pages from the search, but when deleting pages, they should refer to a 404 error. And since this is not a regular page, but some kind of request, then wordpress does not perceive it as a page not found on the server. How to be?

Answer 1

Something like this at the beginning of header.php of your template:

<?php
if(isset($_GET["hmb"])){
  header('Location: /404/');
}

or just return a 404 header with this get:

<?php
if(isset($_GET["hmb"])){
  header("HTTP/1.0 404 Not Found");
}

In theory, Yandex will remove links. but there will be no redirect.