STIGQter STIGQter: STIG Summary: Red Hat Enterprise Linux 8 Security Technical Implementation Guide Version: 2 Release: 8 Benchmark Date: 01 Jul 2026:

RHEL 8 must not accept router advertisements on all IPv6 interfaces by default.

DISA Rule

SV-230542r1017304_rule

Vulnerability Number

V-230542

Group Title

SRG-OS-000480-GPOS-00227

Rule Version

RHEL-08-040262

Severity

CAT II

CCI(s)

Weight

10

Fix Recommendation

Configure RHEL 8 to not accept router advertisements on all IPv6 interfaces by default unless the system is a router.

Add or edit the following line in a system configuration file, in the "/etc/sysctl.d/" directory:

net.ipv6.conf.default.accept_ra=0

Remove any configurations that conflict with the above from the following locations:
/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

Load settings from all system configuration files with the following command:

$ sudo sysctl --system

Check Contents

Verify RHEL 8 does not accept router advertisements on all IPv6 interfaces by default, unless the system is a router.

Note: If IPv6 is disabled on the system, this requirement is not applicable.

Check to see if router advertisements are not accepted by default by using the following command:

$ sudo sysctl net.ipv6.conf.default.accept_ra

net.ipv6.conf.default.accept_ra = 0

If the "accept_ra" 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.default.accept_ra /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.default.accept_ra = 0

If "net.ipv6.conf.default.accept_ra" is not set to "0", is missing or commented out, this is a finding.

If conflicting results are returned, this is a finding.

Vulnerability Number

V-230542

Documentable

False

Rule Version

RHEL-08-040262

Severity Override Guidance

Verify RHEL 8 does not accept router advertisements on all IPv6 interfaces by default, unless the system is a router.

Note: If IPv6 is disabled on the system, this requirement is not applicable.

Check to see if router advertisements are not accepted by default by using the following command:

$ sudo sysctl net.ipv6.conf.default.accept_ra

net.ipv6.conf.default.accept_ra = 0

If the "accept_ra" 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.default.accept_ra /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.default.accept_ra = 0

If "net.ipv6.conf.default.accept_ra" is not set to "0", is missing or commented out, this is a finding.

If conflicting results are returned, this is a finding.

Check Content Reference

M

Target Key

2921