Optimal WordPress Permissions
All WordPress files and folders should have the correct permissions and ownership. It is very important for keep secure your WordPress site.
Files should be 664.
Folders should be 775.
wp-config.php should be 660.
WordPress files permissions can be changed form FTP, SCP clients or from SSH.
In case if you have SSH access to Linux server, login into server and execute following commands:
$ sudo find . -type f -exec chmod 664 {} +
$ sudo find . -type d -exec chmod 775 {} +
$ sudo chmod 660 wp-config.php
