Let’s say we have a document root like:

It’s interesting to note the instructions for this will vary from environment to environment, it depends on which user is looking after apache2, etc.

/var/www/mysite.com/htdocs

Make all files read/write and owned by www-data apache2 user only

root@meine:/var/www/mysite.com/htdocs# find . -type f -exec chown apache2:apache2 {} \; 
root@meine:/var/www/mysite.com/htdocs# find . -type f -exec chmod 644 {} \;

Make all folders accessible Read + Execute, but no write permissions

root@meine:/var/www/mysite.com/htdocs# find . -type d -exec chmod 755 {} \;
root@meine:/var/www/mysite.com/htdocs# find . -type d -exec chown apache2:apache2 {} \;

PLEASE NOTE THIS BREAKS YOUR WORDPRESS ABILITY TO AUTO-UPDATE ITSELF. BUT IT IS MORE SECURE 😀

Note debian users, may need to use www-data:www-data instead.