Referrer Spam Blocker :robot:

Apache, Nginx, IIS, uWSGI, Caddy, Varnish, HAProxy & Lighttpd blacklist + Google Analytics segments to prevent referrer spam traffic

Apache: .htaccess

.htaccess is a configuration file for use on web servers running Apache. This file is usually found in the root “public_html” folder of your website. The .htaccess file uses two modules to prevent referral spam, mod_rewrite and mod_setenvif. Decide which method is most suitable with your Apache server configuration. This file is Apache 2.4 ready, where mod_authz_host got deprecated.

Nginx: referral-spam.conf

IMPORTANT: You must increase the map hash bucket size to support the large domain list. With referral-spam.conf in /etc/nginx, include it globally from within /etc/nginx/nginx.conf:

Add the following to each /etc/nginx/site-available/your-site.conf that needs protection:

Performance Note: This configuration uses a performance-optimized approach with hostname matching instead of thousands of regex patterns. Only one regex is evaluated per request to extract the domain from the Referer header, significantly improving NGINX performance compared to traditional regex-based blocking methods.

Varnish: .refferal-spam.vcl

Add referral-spam.vcl to Varnish 4 default file: default.vcl by adding the following code right underneath your default backend definitions

IIS (Internet Information Services): web.config

The web.config file is located in the root directory of your Windows Server web application.

Caddy (HTTP/2 Web Server with Automatic HTTPS): referral-spam.caddy and referral-spam.caddy2

Move this file next to your Caddy config file, and include it by doing:

# For Caddy 1:
 include ./referral-spam.caddy;
# For Caddy 2:
 import ./referral-spam.caddy2

Then start your caddy server. All the referrers will now be redirected to a 444 HTTP answer

uWSGI: referral_spam.res

Include the file referral_spam.res into your vassal .ini configuration file:

HAProxy: referral-spam.haproxy

Use it in your HAProxy config by adding all domains.txt items, in any frontend, listen or backend block:

Lighttpd: referral-spam.lighttpd.conf

Include this file in your main lighttpd.conf:

Make sure mod_rewrite is enabled in your server.modules:

The configuration blocks referrer spam by redirecting requests with spam referrers. For better performance with large domain lists, consider using mod_magnet.

OpenLiteSpeed: .htaccess

OpenLiteSpeed is Apache-compatible and supports .htaccess files. Simply use the Apache .htaccess file (see Apache section above).

Make sure mod_rewrite is enabled in your OpenLiteSpeed configuration:

• Admin Panel > Server > Modules > mod_rewrite (enable)

Options for Google Analytics 'ghost' spam

The above methods don't stop the Google Analytics ghost referral spam (because they are hitting Analytics directly and don't touching your website). You should use filters in Analytics to prevent ghost referral spam and hide spam form the past. Because Google Analytics segments are limited to 30.000 characters the exclude list is separated into multiple parts.

Navigate to your Google Analytics Admin panel and add these Segments:

Do the same for google-exclude-2.txt. Please note there may be more files in the future.

You can also prevent ghost referral spam by:

• Adding a filter
• Enabeling bot and Spider Filtering

Command Line Interface

Testing

The project includes comprehensive testing and code quality tools:

Tests cover unit testing, configuration generation, domain processing, and file operations. Quality tools include PHPStan (Level 8), PHP CodeSniffer (PSR-12), and Psalm for static analysis.

Programmatic Usage

Intregrate in a Dockerfile

You can also integrate these configuration file in your Docker repo, so you will get always the most updated version when you build your image. For Apache, Nginx, Varnish 4 or IIS add the following line to your Dockerfile

Like it?

• Buy me a beer 🍺