An easy way to make yourself a little less vulnerable to common attack vendors, is to hide the version numbers of the common daemons running on your boxes, and its relativly simple to do.

Hiding the BIND Version

If you follow my Closing Open DNS Servers- BIND tutorial, it shows you how to set the version number to something very different.

PHP

Open up your php.ini (If you have Zend Optimizer on linux - normally /usr/local/Zend/etc/php.ini)

# vi /usr/local/Zend/etc/php.ini

Press / and type expose_php

It should then throw you to the exposure line, edit the line so that it reads:

expose_php = Off

Then save and close the file, finally restart Apache

# service httpd restart

Now your server will no longer return the 'Powered By PHP v' header, please note though that it will be obvious when php pages are in use, this will hide the version from the http headers but doesnt ensure that the version number isnt exposed elsewhere (such as phpinfo pages etc)

Apache 1.3

Open up your httpd.conf (on a cPanel Server - /usr/local/apache/conf/httpd.conf)

Find the line that reads: ServerSignature on

Delete that line and replace it with the following 2 lines:

ServerSignature Off
ServerTokens Prod

Save the file and then restart apache

# service httpd restart

Thats it, whenever a http header/an error page returns, all your server will say is 'Apache' rather than its full version number.