Managing share permissions
Share permissions set the maximum allowable actions available within a shared folder. By default, when you create a share, everyone with access to the network has Read access to the share’s contents. This is an important security change-in previous editions of Windows Server, the default permission was Full Control.
With NTFS and ReFS volumes, you can use file and folder permissions and ownership, in addition to share permissions, to further constrain actions within the share. With FAT volumes, share permissions control only access.