RHEL 10 must not forward Internet Protocol version 4 (IPv4) source-routed packets.
Overview
| Finding ID | Version | Rule ID | IA Controls | Severity |
| V-281342 | RHEL-10-800100 | SV-281342r1167176_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 IPv4 forwarding is enabled and the system is functioning as a router. Accepting source-routed packets in the IPv4 protocol has few legitimate uses. It must be disabled unless it is absolutely required. Satisfies: SRG-OS-000420-GPOS-00186, SRG-OS-000142-GPOS-00073 | ||||
| STIG | Date | |||
| Red Hat Enterprise Linux 10 Security Technical Implementation Guide | 2026-03-11 | |||
Related Frameworks
2 paths across 2 frameworks
Related Frameworks
NIST 800-531 mapping
SC-5
1.00
- DISA · V1R1 · disa_xccdf · related
- DISA · 2025-01-23 · disa_cci_list · equivalent
CCI1 mapping
CCI-002385
1.00
- DISA · V1R1 · disa_xccdf · related
Details
Check Text (C-281342r1167176_chk)
Verify RHEL 10 will not accept IPv4 source-routed packets.
Check the value of the "net.ipv4.conf.all.accept_source_route" variable with the following command:
$ sudo sysctl net.ipv4.conf.all.accept_source_route
net.ipv4.conf.all.accept_source_route = 0
If "net.ipv4.conf.all.accept_source_route" is not set to "0" or is missing, this is a finding.
Fix Text (F-85808r1167175_fix)
Configure RHEL 10 to ignore IPv4 source-routed packets.
Create a configuration file if it does not already exist:
$ sudo vi /etc/sysctl.d/99-ipv4_accept_source.conf
Add the following line to the file:
net.ipv4.conf.all.accept_source_route = 0
Reload settings from all system configuration files with the following command:
$ sudo sysctl --system