In addition to the Application Layer Firewall ('alf') mentioned in the benchmark, macOS also ships with packet filter, or 'pf'. Leveraging 'pf' is beyond the scope of this Benchmark. For more information, please see: - [https://support.apple.com/kb/ht5519](https://support.apple.com/kb/ht5519) - [http://blog.scottlowe.org/2013/05/15/using-pf-on-os-x-mountain-lion/](http://blog.scottlowe.org/2013/05/15/using-pf-on-os-x-mountain-lion/) NOTE: Nessus has not performed this check. Please review the benchmark to ensure target compliance.