RHEL 9 must not have unauthorized IP tunnels configured.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-257950	RHEL-09-252045	SV-257950r991589_rule		Medium

Description
IP tunneling mechanisms can be used to bypass network filtering. If tunneling is required, it must be documented with the information system security officer (ISSO).

STIG	Date
Red Hat Enterprise Linux 9 Security Technical Implementation Guide	2024-06-04

Details

Check Text ( C-61691r925835_chk )
Verify that RHEL 9 does not have unauthorized IP tunnels configured. Determine if the "IPsec" service is active with the following command: $ systemctl status ipsec ipsec.service - Internet Key Exchange (IKE) Protocol Daemon for IPsec Loaded: loaded (/usr/lib/systemd/system/ipsec.service; disabled) Active: inactive (dead) If the "IPsec" service is active, check for configured IPsec connections ("conn"), with the following command: $ grep -rni conn /etc/ipsec.conf /etc/ipsec.d/ Verify any returned results are documented with the ISSO. If the IPsec tunnels are active and not approved, this is a finding.

Check Text ( C-61691r925835_chk )

Verify that RHEL 9 does not have unauthorized IP tunnels configured.

Determine if the "IPsec" service is active with the following command:

$ systemctl status ipsec

ipsec.service - Internet Key Exchange (IKE) Protocol Daemon for IPsec
Loaded: loaded (/usr/lib/systemd/system/ipsec.service; disabled)
Active: inactive (dead)

If the "IPsec" service is active, check for configured IPsec connections ("conn"), with the following command:

$ grep -rni conn /etc/ipsec.conf /etc/ipsec.d/

Verify any returned results are documented with the ISSO.

If the IPsec tunnels are active and not approved, this is a finding.

Fix Text (F-61615r925836_fix)
Remove all unapproved tunnels from the system, or document them with the ISSO.