OL 9 must not enable IPv6 packet forwarding unless the system is a router.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-271880 | OL09-00-006043 | SV-271880r1092352_rule | CCI-000366 | medium |
| Description | ||||
| IP forwarding permits the kernel to forward packets from one network interface to another. The ability to forward packets between two networks is only appropriate for systems acting as routers. | ||||
| STIG | Date | |||
| Oracle Linux 9 Security Technical Implementation Guide | 2025-05-08 | |||
Details
Check Text (C-271880r1092352_chk)
Note: If IPv6 is disabled on the system, this requirement is Not Applicable.
Verify that OL 9 is not performing IPv6 packet forwarding, unless the system is a router.
Check that IPv6 forwarding is disabled using the following commands:
$ 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.
Fix Text (F-75837r1092351_fix)
Configure OL 9 to not allow IPv6 packet forwarding unless the system is a router.
Add or edit the following line in a single system configuration file in the "/etc/sysctl.d/" directory:
net.ipv6.conf.all.forwarding = 0
Load settings from all system configuration files with the following command:
$ sudo sysctl --system