The system must not respond to Internet Control Message Protocol (ICMPv4) echoes sent to a broadcast address.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-22410	GEN003603 M6	SV-38201r1_rule	ECSC-1	Medium

Description
Responding to broadcast ICMP echoes facilitates network mapping and provides a vector for amplification attacks.

STIG	Date
MAC OSX 10.6 Workstation Security Technical Implementation Guide Draft	2013-01-10

Details

Check Text ( C-37658r1_chk )
Open a terminal session and enter the following command to view the value of "net.inet.icmp.bmcastecho". sysctl -a | grep net.inet.icmp.bmcastecho If the value is not set to "1", this is a finding.

Fix Text (F-32899r1_fix)
Open a terminal session and edit the /etc/sysctl.conf file and add the following line. net.inet.icmp.bmcastecho=1 NOTE: If the sysctl.conf file does not exist use the following command to create one. touch /etc/sysctl.conf