The Photon operating system must not respond to IPv4 Internet Control Message Protocol (ICMP) echoes sent to a broadcast address.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-258887	PHTN-40-000224	SV-258887r933722_rule		Medium

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

STIG	Date
VMware vSphere 8.0 vCenter Appliance Photon OS 4.0 Security Technical Implementation Guide	2023-10-29

Details

Check Text ( C-62627r933720_chk )
At the command line, run the following command to verify ICMP echoes sent to a broadcast address are ignored: # /sbin/sysctl net.ipv4.icmp_echo_ignore_broadcasts Example result: net.ipv4.icmp_echo_ignore_broadcasts = 1 If the "net.ipv4.icmp_echo_ignore_broadcasts" kernel parameter is not set to "1", this is a finding.

Fix Text (F-62536r933721_fix)
Navigate to and open: /etc/sysctl.d/zz-stig-hardening.conf Add or update the following line: net.ipv4.icmp_echo_ignore_broadcasts = 1 At the command line, run the following command to load the new configuration: # /sbin/sysctl --load /etc/sysctl.d/zz-stig-hardening.conf Note: If the file zz-stig-hardening.conf does not exist, it must be created.