Details
Starting with macOS 10.15 Apple has provided a control to allow a user to share Apple downloaded content on all Apple devices that are signed in with the same Apple ID. This allows a user to share downloaded Movies, Music or TV shows with other controlled macOS, iOS and iPadOS devices as well as photos with Apple TVs.
With this capability guest users can also use media downloaded on the computer.
The recommended best practice is not to use the computer as a server but to utilize Apple’s cloud storage to download and use content stored there if content stored with Apple is used on multiple devices.
https://support.apple.com/guide/mac-help/set-up-media-sharing-on-mac-mchlp13371337/mac
Rationale:
Disabling Media Sharing reduces the remote attack surface of the system.
Impact:
Media Sharing allows for pre-downloaded content on a Mac to be available to other Apple devices on the same network. Leaving this disabled forces device users to stream or download content from each Apple authorized device. This sharing could even allow unauthorized devices on the same network media access.
Solution
Perform the following to disable Media Sharing:
Graphical Method:
Open System Preferences
Select Sharing
Uncheck Media Sharing
Terminal Method:
Run the following command to disable Media Sharing:
$ sudo -u
example:
$ sudo -u test2 defaults write com.apple.amp.mediasharingd home-sharing-enabled -int 0
Profile Method:
Create or edit a configuration profile with the PayLoadType of com.apple.preferences.sharing.SharingPrefsExtension
Add the key homeSharingUIStatus
Set the key to
Add the key legacySharingUIStatus
Set the key to
Add the key mediaSharingUIStatus
Set the key to
Supportive Information
The following resource is also helpful.
This security hardening control applies to the following category of controls within NIST 800-53: Configuration Management, Identification and Authentication.This control applies to the following type of system Unix.