DISA STIGS Viewer

AlmaLinux OS 9 must not have unauthorized IP tunnels configured.

Overview

Finding ID Version Rule ID IA Controls Severity
V-269250 ALMA-09-019270 SV-269250r1050132_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
CloudLinux AlmaLinux OS 9 Security Technical Implementation Guide 2025-05-22

Details

Check Text (C-73281r1049382_chk)
Verify that AlmaLinux OS 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; preset: disabled)
Active: inactive (dead)

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

$ grep -ri conn /etc/ipsec.conf /etc/ipsec.d/ | grep -v '#'

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-73182r1048127_fix)
Remove all unapproved tunnels from the system, or document them with the ISSO.