STIGQter STIGQter: STIG Summary: Tri-Lab Operating System Stack (TOSS) 4 Security Technical Implementation Guide Version: 2 Release: 6 Benchmark Date: 01 Jul 2026:

TOSS must not forward IPv4 source-routed packets by default.

DISA Rule

SV-253124r991589_rule

Vulnerability Number

V-253124

Group Title

SRG-OS-000480-GPOS-00227

Rule Version

TOSS-04-040830

Severity

CAT II

CCI(s)

Weight

10

Fix Recommendation

Configure TOSS to not forward IPv4 source-routed packets by default with the following command:

$ sudo sysctl -w net.ipv4.conf.default.accept_source_route=0

If "0" is not the system's default value then add or update the following line in the appropriate file under "/etc/sysctl.d":

net.ipv4.conf.default.accept_source_route=0

Check Contents

Verify TOSS does not accept IPv4 source-routed packets by default.

Note: If IPv4 is disabled on the system, this requirement is Not Applicable.

Check the value of the accept source route variable with the following command:

$ sudo 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", a line is not returned, or the line is commented out, this is a finding.

Vulnerability Number

V-253124

Documentable

False

Rule Version

TOSS-04-040830

Severity Override Guidance

Verify TOSS does not accept IPv4 source-routed packets by default.

Note: If IPv4 is disabled on the system, this requirement is Not Applicable.

Check the value of the accept source route variable with the following command:

$ sudo 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", a line is not returned, or the line is commented out, this is a finding.

Check Content Reference

M

Target Key

5469