Everybody has rights to access my folders in /shares

I found if I use a third party webdav client (like goodreader in iphone), I (and anybody else) can access (without any permission) my /shares folder, as well as the the “.mediacrawler” folder and anything in “.mediacrawler”.

Is there anything wrong with my MLB?

Has anybody tried to use goodreader (by choosing ‘Any WebDAV Server’ option) to access your MBL ?  In my case, I can access the /shares folder (although, not the sub-folder under it) and /shares/.mediacrawler, without any authentication. 

The URL-address is http:// ip-address-of-your-MBL/shares.