Block referrer spam from the SEMalt botnet

We are trialling the following solution for blocking what is fast becoming a scourge of the web; SEMalt referrer spam.
It’s been added to the .htaccess file on one of our personal sites, and we’ll see how it does there before implementing these measures on the rest of the sites we manage. Update to follow.

UPDATE: While blocking at the server IS working, there is much more to blocking this type of spam which is detailed here and here.

Reduce the number of malicious URL requests that hit your website

If your site runs on Apache and you’re familiar with .htaccess, the 5G Blacklist is an effective way to secure your site against malicious HTTP activity.

[Update: The 6G Blacklist is now available.]

The 5G Blacklist is a simple, flexible blacklist that checks all URI requests against a series of carefully constructed HTAccess directives. This happens quietly behind the scenes at the server level, saving resources for stuff like PHP and MySQL for all blocked requests.

Simply add the following code to your site’s .htaccess file. Make sure you make a copy of your existing file before making any changes.