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 allow IPv4 ICMP redirect messages.

DISA Rule

SV-230536r1208868_rule

Vulnerability Number

V-230536

Group Title

SRG-OS-000480-GPOS-00227

Rule Version

RHEL-08-040220

Severity

CAT II

CCI(s)

CCI-000366 - Implement the security configuration settings.

Weight

Fix Recommendation

Configure RHEL 8 to not allow interfaces to perform IPv4 ICMP redirects.

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

net.ipv4.conf.all.send_redirects=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 IPv4 ICMP redirect messages.

Check the value of the "all send_redirects" variables with the following command:

$ sudo sysctl net.ipv4.conf.all.send_redirects
net.ipv4.conf.all.send_redirects = 0

If the returned line does not have a value of "0", or a line is not returned, this is a finding.

Check that the configuration files are present to enable this network parameter.

$ sudo grep -r net.ipv4.conf.all.send_redirects /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.ipv4.conf.all.send_redirects = 0

If "net.ipv4.conf.all.send_redirects" 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-230536

Documentable

False

Rule Version

RHEL-08-040220

Severity Override Guidance

Check Content Reference

Target Key

2921