As the title says. I have a folder, which I added to my Shared Folder list under System Preferences > Sharing that I do not want to broadcast publicly. I'm the owner of the folder and my access is "Read & Write" and the Everyone group is set to "No Access".
Using a second computer I can navigate to this share, logged in as "Guest", and I can still see and navigate this private share.
I removed all my shares, turned off and back on again (AFP file sharing service) and instead of defining my share points in the System Preferences, I used ⌘I (Get Info) and checked the "Shared folder" checkbox. I then applied the same permissions at the bottom of the Get Info window with the same results. I can still see and navigate the private share over the network.
Best Answer
Any folder added to your shared folder list is broadcast publicly. If you don't want it to be visible to guest users, remove it from your shared folder list. You will still be able to access it by logging in as a registered user, using your user name and password. If you log in as a registered user, you will be able to see all your files, but a guest can only see files in the shared folder list.