The firewall implementation must implement NAT to ensure endpoint internal IPv4 addresses are not visible to external untrusted networks.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-37338	SRG-NET-999999-FW-000168	SV-49099r1_rule		Low

Description
Network Address Translation (NAT) works well with the implementation of RFC 1918 addressing scheme. It also has the privacy benefit of hiding real internal addresses. An attacker can learn more about a site's private network once the real IP addresses of the hosts within have been discovered.

STIG	Date
Firewall Security Requirements Guide	2013-04-24

Details

Check Text ( C-45586r1_chk )
If NAT is implemented on the premise router, this is not a finding. Review the firewall or premise router configuration to determine if NAT has been implemented. If NAT is not implemented on the firewall, this is a finding.

Fix Text (F-42263r1_fix)
Implement NAT on the firewall or premise router for NIPRNet enclaves.