Hide Apache ServerSignature / ServerTokens / PHP X-Powered-By
By default almost all Apache installation shows sensitive server information with Apache version number, server operating system details, installed Apache modules, PHP-version and so on. Attackers can use this information when performing attacks.
Some examples howto check server information that Apache sends
Error page
Use lynx
$ lynx -head -mime_header http://www.ubuntu.com
HTTP/1.0 200 OK
Date: Fri, 20 Nov 2009 09:25:46 GMT
Server: Apache/2.2.8 (Ubuntu)...