The SUSE operating system must not forward Internet Protocol version 4 (IPv4) source-routed packets by default.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-217289	SLES-12-030370	SV-217289r991589_rule	CCI-000366	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.
STIG			Date
SUSE Linux Enterprise Server 12 Security Technical Implementation Guide			2025-05-14

Related Frameworks

4 paths across 3 frameworks

NIST 800-531 mapping

CM-6

1.00

DISA · 3 · disa_xccdf · related
DISA · 2025-01-23 · disa_cci_list · equivalent

NIST 800-1712 mappings

3.4.1

1.00

DISA · 3 · disa_xccdf · related
DISA · 2025-01-23 · disa_cci_list · equivalent
NIST · Rev 2 (Feb 2020, errata Jan 2021) · nist_800_171_app_d · equivalent

3.4.2

1.00

DISA · 3 · disa_xccdf · related
DISA · 2025-01-23 · disa_cci_list · equivalent
NIST · Rev 2 (Feb 2020, errata Jan 2021) · nist_800_171_app_d · equivalent

CCI1 mapping

CCI-000366

1.00

DISA · 3 · disa_xccdf · related

Details

Check Text (C-217289r991589_chk)

Verify the SUSE operating system does not accept IPv4 source-routed packets by default. Check the value of the default accept source route variable with the following command: # sysctl net.ipv4.conf.default.accept_source_route net.ipv4.conf.default.accept_source_route = 0 If the returned line does not have a value of "0" this is a finding.

Fix Text (F-18515r370024_fix)

Configure the SUSE operating system to the required kernel parameter by adding the following line to "/etc/sysctl.conf" (or modify the line to have the required value): net.ipv4.conf.default.accept_source_route = 0 Run the following command to apply this value: # sysctl --system