Skip to main content

How to block OutsellURLValidator

Operated by Outsell Corporation. Validating client website URLS to monitor for hosting/provider changes

How it identifies itself

OutsellURLValidator

robots.txt

What the agent asks to be told. It obeys this or it does not — nothing enforces it.

robots.txt
User-agent: OutsellURLValidator
Disallow: /

nginx

In the server block, then reload.

nginx
# In the server block. 403 rather than 444: a closed connection tells the
# operator nothing, and an agent that gets a status code can log it.
if ($http_user_agent ~* "(OutsellURLValidator)") {
    return 403;
}

Apache

In .htaccess or the vhost.

Apache
BrowserMatchNoCase "OutsellURLValidator" bad_bot

<RequireAll>
    Require all granted
    Require not env bad_bot
</RequireAll>

Cloudflare

Security → WAF → Custom rules.

Cloudflare
# Security → WAF → Custom rules, action: Block
(http.user_agent contains "OutsellURLValidator")

WordPress

A child theme's functions.php, or a small plugin.

WordPress
// functions.php of a child theme, or a small plugin. Runs before WordPress
// builds the page, so a blocked agent costs one PHP process and no queries.
add_action('init', function () {
    $agent = $_SERVER['HTTP_USER_AGENT'] ?? '';

    foreach (['OutsellURLValidator'] as $needle) {
        if (stripos($agent, $needle) !== false) {
            status_header(403);
            exit('Blocked: OutsellURLValidator');
        }
    }
});

robots.txt is a request. The rules below it are the wall.

OutsellURLValidator publishes a token, so the directive above will work for as long as it keeps honouring it — and nothing except its own good manners makes it. The server rules match on a header the requester sets, which stops the agent that says who it is and not the one that copies somebody else's name. Botscope verifies identity against DNS and published address ranges, records which check decided each request, and shows you the ones that lied.

Others like it

Everything we know about OutsellURLValidator