RHEL 10 must not forward Internet Protocol version 6 (IPv6) source-routed packets.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-281356 | RHEL-10-800240 | SV-281356r1167218_rule | CCI-002385 | medium |
| Description | ||||
| Source-routed packets allow the source of the packet to suggest that routers forward the packet along a different path than configured on the router, which can be used to bypass network security measures. This requirement applies only to the forwarding of source-routed traffic, such as when forwarding is enabled and the system is functioning as a router. Satisfies: SRG-OS-000420-GPOS-00186, SRG-OS-000142-GPOS-00087 | ||||
| STIG | Date | |||
| Red Hat Enterprise Linux 10 Security Technical Implementation Guide | 2026-03-11 | |||
Details
Check Text (C-281356r1167218_chk)
Note: If IPv6 is disabled on the system, this requirement is not applicable.
Verify RHEL 10 does not accept IPv6 source-routed packets.
Check the value of the "net.ipv6.conf.all.accept_source_route" variable with the following command:
$ sudo sysctl net.ipv6.conf.all.accept_source_route
net.ipv6.conf.all.accept_source_route = 0
If "net.ipv6.conf.all.accept_source_route" is not set to "0" or is missing, this is a finding.
Fix Text (F-85822r1167217_fix)
Configure RHEL 10 to not accept IPv6 source-routed packets.
Create a configuration file if it does not already exist:
$ sudo vi /etc/sysctl.d/ipv6_accept_source_route.conf
Add the following line to the file:
net.ipv6.conf.all.accept_source_route = 0
Reload settings from all system configuration files with the following command:
$ sudo sysctl --system