Ensure Media Sharing Is Disabled

LowLevel 2Automatedmacos

Description

Starting with macOS 10.15, Apple has provided a control which permits a user to share Apple-downloaded content on all Apple devices that are signed in with the same Apple ID. This allows users 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 in order 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 Disabling Media Sharing reduces the remote attack surface of the system.

How it is checked

Audit method: Shell command

shell

/usr/bin/osascript -l JavaScript <<'EOS'
function run() {
  let pref1 = ObjC.unwrap($.NSUserDefaults.alloc.initWithSuiteName('com.apple.applicationaccess').objectForKey('allowMediaSharing'))
  let pref2 = ObjC.unwrap($.NSUserDefaults.alloc.initWithSuiteName('com.apple.applicationaccess').objectForKey('allowMediaSharingModification'))
  if ( pref1 == 0 && pref2 == 0 ) {
    return("true")
  } else {
    return("false")
  }
}
EOS

Expected output: true

How it is fixed

Fix method: Guidance or infrastructure patch

Profile Method: Create or edit a configuration profile with the following information: 1. The PayloadType string is com.apple.preferences.sharing.SharingPrefsExtension 2. The key to include is homeSharingUIStatus 3. The key must be set to <integer>0</integer> 4. The key to also include is legacySharingUIStatus 5. The key must be set to <integer>0</integer> 6. The key to also include is mediaSharingUIStatus 7. The key must be set to <integer>0</integer>

Properties

Operating systems: macos-14
Tags: macossonoma
Reference: CIS Apple macOS 14.0 Sonoma Benchmark v3.1.0 - 2.3.3.9 Ensure Media Sharing Is Disabled

Check this host

Run this on a machine you are allowed to audit. The scan is read-only.

shell

tmaegis scan --target macos --level 2