Only essential services must be allowed through firewall.

From MAC OSX 10.6 Workstation Security Technical Implementation Guide

Part of OSX00455-Allow essential services through firewall

Associated with IA controls: ECND-1

SV-38563r1_rule Only essential services must be allowed through firewall.

Vulnerability discussion

Allowing only essential services through the firewall alleviates the potential for unwanted services to run on the system, and cuts down on system usage.

Check content

Open System Preferences->Security. Select Firewall tab. Select Advanced (firewall should be started). Either "Block all incoming connections" should be checked or only essential services and applications should be allowed. If not, this is a finding.

Fix text

Open System Preferences -> Security. Select Firewall tab. Select the Advanced button. Check "Block all incoming connections" or remove any non-essential services and applications.

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