| Verify RHEL 8 is not performing IPv6 packet forwarding, unless the system is a router. |
Note: If IPv6 is disabled on the system, this requirement is Not Applicable.
Check that IPv6 forwarding is disabled using the following commands:
$ sudo sysctl net.ipv6.conf.all.forwarding
net.ipv6.conf.all.forwarding = 0
If the IPv6 forwarding value is not "0" and is not documented with the Information System Security Officer (ISSO) as an operational requirement, this is a finding.
Check that the configuration files are present to enable this network parameter.
$ sudo grep -r net.ipv6.conf.all.forwarding /run/sysctl.d/*.conf /usr/local/lib/sysctl.d/*.conf /usr/lib/sysctl.d/*.conf /lib/sysctl.d/*.conf /etc/sysctl.conf /etc/sysctl.d/*.conf
/etc/sysctl.d/99-sysctl.conf: net.ipv6.conf.all.forwarding = 0
If "net.ipv6.conf.all.forwarding" is not set to "0", is missing or commented out, this is a finding.
If conflicting results are returned, this is a finding.