How to block Yahoo Link Preview
Operated by Yahoo. Yahoo Link Preview's bot fetches data from URLs shared on Yahoo platforms.
How it identifies itself
Mozilla/5.0 (compatible; Yahoo Link Preview; https://help.yahoo.com/kb/mail/yahoo-link-preview-SLN23615.html)
robots.txt
What the agent asks to be told. It obeys this or it does not — nothing enforces it.
User-agent: Yahoo Link Preview 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 ~* "(Yahoo Link Preview|Yahoo!)") {
return 403;
}
Apache
In .htaccess or the vhost.
BrowserMatchNoCase "Yahoo Link Preview" bad_bot
BrowserMatchNoCase "Yahoo!" 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 "Yahoo Link Preview") or (http.user_agent contains "Yahoo!")
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 (['Yahoo Link Preview', 'Yahoo!'] as $needle) {
if (stripos($agent, $needle) !== false) {
status_header(403);
exit('Blocked: Yahoo Link Preview');
}
}
});
robots.txt is a request. The rules below it are the wall.
Yahoo Link Preview 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.