# Block all extensions except png|jpg|pdf|jiff
<FilesMatch "\.(?!(png|jpg|pdf|gif)$)[^.]+$">
    Order Allow,Deny
    Deny from all
</FilesMatch>
# Disable execution of any script
<FilesMatch "\.(php|php[3457]?|phtml|pl|py|jsp|asp|aspx|cgi)$">
    Order Allow,Deny
    Deny from all
</FilesMatch>