Details
Internet Sharing uses the open source natd process to share an internet connection with other computers and devices on a local network. This allows the Mac to function as a router and share the connection to other, possibly unauthorized, devices.
Rationale:
Disabling Internet Sharing reduces the remote attack surface of the system.
Impact:
Internet sharing allows the computer to function as a router and other computers to use it for access. This can expose both the computer itself and the networks it is accessing to unacceptable access from unapproved devices.
Solution
Perform the following to implement the prescribed state:
Open System Preferences
Select Sharing
Uncheck Internet Sharing
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.This control applies to the following type of system Unix.