Vulnerability Discussion

If the system does not require Internet Sharing, support for it is nonessential and must be disabled.

The information system must be configured to provide only essential capabilities. Disabling Internet Sharing helps prevent unauthorized connection of devices, transfer of information, and tunneling.

Check

Verify the macOS system is configured to disable Internet Sharing with the following command:

/usr/bin/osascript -l JavaScript << EOS
$.NSUserDefaults.alloc.initWithSuiteName('com.apple.MCX')\
.objectForKey('forceInternetSharingOff').js
EOS

If the result is not "true", this is a finding.

Fix

Configure the macOS system to disable Internet Sharing by installing the "com.apple.MCX" configuration profile.