Information
Gatekeeper is Apple's application white-listing control that restricts downloaded applications from launching. It functions as a control to limit applications from unverified sources from running without authorization.
Rationale:
Disallowing unsigned software will reduce the risk of unauthorized or malicious applications from running on the system.
Solution
Perform the following to implement the prescribed state:
Graphical Method:
Open System Preferences
Select Security & Privacy
Select General
Set Allow apps downloaded from to App Store and identified developers
Terminal Method:
Run the following command to enable Gatekeeper to allow applications from App Store and identified developers:
$ sudo spctl --master-enable