The systems local firewall must implement a deny-all, allow-by-exception policy.

From Oracle Linux 5 Security Technical Implementation Guide

Associated with: CCI-001109

SV-63141r1_rule The systems local firewall must implement a deny-all, allow-by-exception policy.

Vulnerability discussion

A local firewall protects the system from exposing unnecessary or undocumented network services to the local enclave. If a system within the enclave is compromised, firewall protection on an individual system continues to protect it from attack.

Check content

Check the firewall rules for a default deny rule. # iptables --list Example of a rule meeting this criteria: REJECT all -- anywhere anywhere reject-with icmp-host-prohibited A rule using DROP is also acceptable. The default rule should be the last rule of a table and match all traffic. If there is no default deny rule, this is a finding.

Fix text

Edit "/etc/sysconfig/iptables" and add a default deny rule. An example of a default deny rule: -A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited Restart the iptable service. # service iptables restart

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