How to block Expanse
Operated by Palo Alto Networks. is a security scanner operated by Palo Alto Networks that continuously scans the global IPv4 address space multiple times per day. The scanner identifies and maps… Security Scanner Scans websites for security vulnerabilities, threats, and configuration weaknesses
How it identifies itself
Expanse, a Palo Alto Networks company, searches across the global IPv4 space multiple times per day to identify customers' presences on the Internet. If you would like to be excluded from our scans, please send IP addresses/domains to: [email protected]
robots.txt
What the agent asks to be told. It obeys this or it does not — nothing enforces it.
User-agent: Expanse 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 ~* "(Expanse|Expanse, a Palo Alto Networks company, searches across the global IPv4 space multiple times per day to identify customers' presences on the Internet.)") {
return 403;
}
Apache
In .htaccess or the vhost.
BrowserMatchNoCase "Expanse" bad_bot
BrowserMatchNoCase "Expanse, a Palo Alto Networks company, searches across the global IPv4 space multiple times per day to identify customers' presences on the Internet." 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 "Expanse") or (http.user_agent contains "Expanse, a Palo Alto Networks company, searches across the global IPv4 space multiple times per day to identify customers' presences on the Internet.")
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 (['Expanse', 'Expanse, a Palo Alto Networks company, searches across the global IPv4 space multiple times per day to identify customers\' presences on the Internet.'] as $needle) {
if (stripos($agent, $needle) !== false) {
status_header(403);
exit('Blocked: Expanse');
}
}
});
robots.txt is a request. The rules below it are the wall.
Expanse 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.