Correct file permissions for WordPress

When you setup WP you (the webserver) may need write access to the files. So the access rights may need to be loose.

chown www-data:www-data  -R * # Let Apache be owner
find . -type d -exec chmod 755 {} \;  # Change directory permissions rwxr-xr-x
find . -type f -exec chmod 644 {} \;  # Change file permissions rw-r--r--

After the setup you should tighten the access rights, according to Hardening WordPress all files except for wp-content should be writable by your user account only. wp-content must be writable by www-data too.

chown <username>:<username>  -R * # Let your useraccount be owner
chown www-data:www-data wp-content # Let apache be owner of wp-content

Maybe you want to change the contents in wp-content later on. In this case you could

• temporarily change to the user to www-data with su,
• give wp-content group write access 775 and join the group www-data or
• give your user the access rights to the folder using ACLs.

Whatever you do, make sure the files have rw permissions for www-data.

Giving the full access to all wp files to www-data user (which is in this case the web server user) can be dangerous. So rather do NOT do this:

chown www-data:www-data -R *

It can be useful however in the moment when you're installing or upgrading WordPress and its plug-ins. But when you finished it's no longer a good idea to keep wp files owned by the web server.

It basically allows the web server to put or overwrite any file in your website. This means that there is a possibility to take over your site if someone manage to use the web server (or a security hole in some .php script) to put some files in your website.

To protect your site against such an attack you should to the following:

All files should be owned by your user account, and should be writable by you. Any file that needs write access from WordPress should be writable by the web server, if your hosting set up requires it, that may mean those files need to be group-owned by the user account used by the web server process.

/

The root WordPress directory: all files should be writable only by your user account, except .htaccess if you want WordPress to automatically generate rewrite rules for you.

/wp-admin/

The WordPress administration area: all files should be writable only by your user account.

/wp-includes/

The bulk of WordPress application logic: all files should be writable only by your user account.

/wp-content/

User-supplied content: intended to be writable by your user account and the web server process.

Within /wp-content/ you will find:

/wp-content/themes/

Theme files. If you want to use the built-in theme editor, all files need to be writable by the web server process. If you do not want to use the built-in theme editor, all files can be writable only by your user account.

/wp-content/plugins/

Plugin files: all files should be writable only by your user account.

Other directories that may be present with /wp-content/ should be documented by whichever plugin or theme requires them. Permissions may vary.

Source and additional information: http://codex.wordpress.org/Hardening_WordPress