How to block WPMU DEV Broken Link Checker
Operated by WPMUDEV. Runs a full scan of a site to find any broken links
How it identifies itself
Mozilla/5.0 (compatible; WPMU DEV Hub/2.0; +https://wpmudev.com)
robots.txt
What the agent asks to be told. It obeys this or it does not — nothing enforces it.
User-agent: WPMU Disallow: /
nginx
In the server block, then reload.
# 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 ~* "(WPMU DEV Broken Link Checker|WPMU|WPMU DEV Broken Link Checker Local EngineSimplePie)") {
return 403;
}
Apache
In .htaccess or the vhost.
BrowserMatchNoCase "WPMU DEV Broken Link Checker" bad_bot
BrowserMatchNoCase "WPMU" bad_bot
BrowserMatchNoCase "WPMU DEV Broken Link Checker Local EngineSimplePie" bad_bot
<RequireAll>
Require all granted
Require not env bad_bot
</RequireAll>
Cloudflare
Security → WAF → Custom rules.
# Security → WAF → Custom rules, action: Block (http.user_agent contains "WPMU DEV Broken Link Checker") or (http.user_agent contains "WPMU") or (http.user_agent contains "WPMU DEV Broken Link Checker Local EngineSimplePie")
WordPress
A child theme's functions.php, or a small plugin.
// 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 (['WPMU DEV Broken Link Checker', 'WPMU', 'WPMU DEV Broken Link Checker Local EngineSimplePie'] as $needle) {
if (stripos($agent, $needle) !== false) {
status_header(403);
exit('Blocked: WPMU DEV Broken Link Checker');
}
}
});
robots.txt is a request. The rules below it are the wall.
WPMU DEV Broken Link Checker 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.