TOSS must not be performing packet forwarding unless the system is a router.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-252941	TOSS-04-010390	SV-252941r824147_rule		Medium

Description
Routing protocol daemons are typically used on routers to exchange network topology information with other routers. If this software is used when not required, system network information may be unnecessarily transmitted across the network.

STIG	Date
Tri-Lab Operating System Stack (TOSS) 4 Security Technical Implementation Guide	2022-08-29

Details

Check Text ( C-56394r824145_chk )

Verify TOSS is not performing packet forwarding unless the system is a router. If the system is a router (sometimes called a gateway) this requirement is Not Applicable. Note: If either IPv4 or IPv6 is disabled on the system, this requirement only applies to the active internet protocol version. Check to see if IP forwarding is enabled using the following commands: $ sudo sysctl net.ipv4.ip_forward net.ipv4.ip_forward = 0 $ sudo sysctl net.ipv6.conf.all.forwarding net.ipv6.conf.all.forwarding = 0 If IP 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-56344r824146_fix)
Configure TOSS to not allow packet forwarding, unless the system is a router with the following commands: $ sudo sysctl -w net.ipv4.ip_forward=0 $ sudo sysctl -w net.ipv6.conf.all.forwarding=0 If "0" is not the system's default value then add or update the following lines in the appropriate file under "/etc/sysctl.d": net.ipv4.ip_forward=0 net.ipv6.conf.all.forwarding=0