Prevent DNS Injections Apache Web Server

To prevent DNS Injection attacks, 

which are attacks that can inject fake DNS names into your server's cache, you need to add another module to Apache. 
Follow these steps

Open a terminal window

Issue the command sudo apt-get -y install libapache2-mod-spamhaus

After the installation completes, issue the command sudo touch /etc/spamhaus.wl.

Issue the command sudo chown -R www-data:root /var/log/apache2/evasive.

With the module installed, open the /etc/apache2/apache2.conf file (using sudo and your favorite text editor) and append the following to the bottom of your configuration file:

  MS_METHODS POST,PUT,OPTIONS,CONNECT 
  MS_WhiteList /etc/spamhaus.wl 
  MS_CacheSize 256 

Save the apache2.conf file and restart Apache so the new module will take effect