The SUSE operating system must not be performing packet forwarding unless the system is a router.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-77501	SLES-12-030430	SV-92197r3_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
SLES 12 Security Technical Implementation Guide	2018-09-27

Details

Check Text ( C-77061r1_chk )
Verify the SUSE operating system is not performing packet forwarding, unless the system is a router. Check to see if IP forwarding is enabled using the following command: # sysctl net.ipv4.ip_forward net.ipv4.ip_forward = 0 If IP forwarding value is "1" and the system is hosting any application, database, or web servers, this is a finding.

Fix Text (F-84143r3_fix)
Configure the SUSE operating system to the required kernel parameter upon boot by adding the following line to "/etc/sysctl.conf" (or modify the line to have the required value): net.ipv4.ip_forward=0 Run the following command to apply this value: # sysctl --system