The Photon operating system must not perform multicast packet forwarding.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-239182	PHTN-67-000111	SV-239182r675354_rule		Medium

Description
Routing protocol daemons are typically used on routers to exchange network topology information with other routers. If this software is used when not required, system network information may be unnecessarily transmitted across the network.

STIG	Date
VMware vSphere 6.7 Photon OS Security Technical Implementation Guide	2021-04-15

Details

Check Text ( C-42393r675352_chk )
At the command line, execute the following command: # /sbin/sysctl -a --pattern "net.ipv[4\|6].conf.(all\|default\|eth.*).mc_forwarding" Expected result: net.ipv4.conf.all.mc_forwarding = 0 net.ipv4.conf.default.mc_forwarding = 0 net.ipv4.conf.eth0.mc_forwarding = 0 net.ipv6.conf.all.mc_forwarding = 0 net.ipv6.conf.default.mc_forwarding = 0 net.ipv6.conf.eth0.mc_forwarding = 0 If the output does not match the expected result, this is a finding. Note: The number of "ethx" lines returned is dependent on the number of interfaces. Every "ethx" entry must be set to "0".

Check Text ( C-42393r675352_chk )

At the command line, execute the following command:

# /sbin/sysctl -a --pattern "net.ipv[4|6].conf.(all|default|eth.*).mc_forwarding"

Expected result:

net.ipv4.conf.all.mc_forwarding = 0
net.ipv4.conf.default.mc_forwarding = 0
net.ipv4.conf.eth0.mc_forwarding = 0
net.ipv6.conf.all.mc_forwarding = 0
net.ipv6.conf.default.mc_forwarding = 0
net.ipv6.conf.eth0.mc_forwarding = 0

If the output does not match the expected result, this is a finding.

Note: The number of "ethx" lines returned is dependent on the number of interfaces. Every "ethx" entry must be set to "0".

Fix Text (F-42352r675353_fix)
At the command line, execute the following command: # for SETTING in $(/sbin/sysctl -aN --pattern "net.ipv[4\|6].conf.(all\|default\|eth.*).mc_forwarding"); do sed -i -e "/^${SETTING}/d" /etc/sysctl.conf;echo $SETTING=0>>/etc/sysctl.conf; done