The perimeter router must be configured to filter traffic destined to the enclave in accordance with the guidelines contained in DoD Instruction 8551.1.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-207135	SRG-NET-000205-RTR-000003	SV-207135r604135_rule		Medium

Description
Vulnerability assessments must be reviewed by the System Administrator, and protocols must be approved by the Information Assurance (IA) staff before entering the enclave. Access control lists (ACLs) are the first line of defense in a layered security approach. They permit authorized packets and deny unauthorized packets based on port or service type. They enhance the posture of the network by not allowing packets to reach a potential target within the security domain. The lists provided are highly susceptible ports and services that should be blocked or limited as much as possible without adversely affecting customer requirements. Auditing packets attempting to penetrate the network but that are stopped by an ACL will allow network administrators to broaden their protective ring and more tightly define the scope of operation. If the perimeter is in a Deny-by-Default posture and what is allowed through the filter is in accordance with DoD Instruction 8551.1, and if the permit rule is explicitly defined with explicit ports and protocols allowed, then all requirements related to PPS being blocked would be satisfied.

Description

Vulnerability assessments must be reviewed by the System Administrator, and protocols must be approved by the Information Assurance (IA) staff before entering the enclave. Access control lists (ACLs) are the first line of defense in a layered security approach. They permit authorized packets and deny unauthorized packets based on port or service type. They enhance the posture of the network by not allowing packets to reach a potential target within the security domain. The lists provided are highly susceptible ports and services that should be blocked or limited as much as possible without adversely affecting customer requirements. Auditing packets attempting to penetrate the network but that are stopped by an ACL will allow network administrators to broaden their protective ring and more tightly define the scope of operation. If the perimeter is in a Deny-by-Default posture and what is allowed through the filter is in accordance with DoD Instruction 8551.1, and if the permit rule is explicitly defined with explicit ports and protocols allowed, then all requirements related to PPS being blocked would be satisfied.

STIG	Date
Router Security Requirements Guide	2021-03-16

Details

Check Text ( C-7396r382343_chk )
This requirement is not applicable for the DoDIN Backbone. Review the router configuration to verify that the ingress filter is in accordance with DoD 8551. If the router does not filter traffic in accordance with the guidelines contained in DoD 8551, this is a finding.

Fix Text (F-7396r539636_fix)
This requirement is not applicable for the DoDIN Backbone. Configure the router to use ingress ACLs to restrict traffic in accordance with the guidelines contained in DOD Instruction 8551.1 for all services and protocols required for operational commitments.