The system must not send IPv4 ICMP redirects.

From MAC OSX 10.6 Workstation Security Technical Implementation Guide

Associated with IA controls: ECSC-1

Associated with: CCI-001551

SV-38205r1_rule The system must not send IPv4 ICMP redirects.

Vulnerability discussion

ICMP redirect messages are used by routers to inform hosts of a more direct route existing for a particular destination. These messages contain information from the system's route table possibly revealing portions of the network topology.

Check content

Open a terminal session and enter the following command to view the value of "net.inet.ip.redirect". sysctl -a | grep net.inet.ip.redirect If the value of "net.inet.ip.redirect" is not set to "0", this is a finding.

Fix text

Open a terminal session and edit the /etc/sysctl.conf file and add the following line. net.inet.ip.redirect=0 NOTE: If the sysctl.conf file does not exist use the following command to create one. touch /etc/sysctl.conf

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