AIX must be configured with a default gateway for IPv4 if the system uses IPv4, unless the system is a router.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-215262	AIX7-00-002063	SV-215262r508663_rule		Medium

Description
If a system has no default gateway defined, the system is at increased risk of man-in-the-middle, monitoring, and Denial of Service attacks.

STIG	Date
IBM AIX 7.x Security Technical Implementation Guide	2022-06-06

Details

Check Text ( C-16460r294237_chk )
Check the system for an IPv4 default route using command: # netstat -r |grep default default 10.11.20.1 UG 1 1811 en0 - - If a default route is not defined, this is a finding.

Fix Text (F-16458r294238_fix)
Set a default gateway for IPv4 using: # route add 0