UCF STIG Viewer Logo

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-239182r816670_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 2022-06-17

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".
Fix Text (F-42352r816669_fix)
Open /etc/sysctl.conf with a text editor.

Add or update the following lines:

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

Run the following command to load the new setting:

# /sbin/sysctl --load