The router must be configured to only permit management traffic that ingresses and egresses the OOBM interface.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-78351	SRG-NET-000205-RTR-000012	SV-93057r1_rule		Medium

Description
The OOBM access switch will connect to the management interface of the managed network elements. The management interface can be a true OOBM interface or a standard interface functioning as the management interface. In either case, the management interface of the managed network element will be directly connected to the OOBM network. An OOBM interface does not forward transit traffic, thereby providing complete separation of production and management traffic. Since all management traffic is immediately forwarded into the management network, it is not exposed to possible tampering. The separation also ensures that congestion or failures in the managed network do not affect the management of the device. If the device does not have an OOBM port, the interface functioning as the management interface must be configured so that management traffic does not leak into the managed network and that production traffic does not leak into the management network.

Description

The OOBM access switch will connect to the management interface of the managed network elements. The management interface can be a true OOBM interface or a standard interface functioning as the management interface. In either case, the management interface of the managed network element will be directly connected to the OOBM network. An OOBM interface does not forward transit traffic, thereby providing complete separation of production and management traffic. Since all management traffic is immediately forwarded into the management network, it is not exposed to possible tampering. The separation also ensures that congestion or failures in the managed network do not affect the management of the device. If the device does not have an OOBM port, the interface functioning as the management interface must be configured so that management traffic does not leak into the managed network and that production traffic does not leak into the management network.

STIG	Date
Router Security Requirements Guide	2018-01-26

Details

Check Text ( C-77911r1_chk )
Step 1: Verify that the managed interface has an inbound and outbound ACL configured. Step 2: Verify that the ingress ACL blocks all transit traffic—that is, any traffic not destined to the router itself. In addition, traffic accessing the managed router should be originated at the NOC. Note that the destination used by any host within the management network to access the managed router must be via the management interface. The loopback should not be a valid address since these prefixes would not be advertised into the management network IGP domain. This could only be possible if the managed network elements had an IGP adjacency with the managed network, which should not be the case. Step 3: Verify that the egress ACL blocks any traffic not originated by the managed router. In addition, traffic egressing the management interface must be destined to the NOC. Caveat: This requirement is only applicable if the management interface connected to the OOBM access switch is a routed interface. If the management interface is a true OOBM interface, this requirement is not applicable. If the router does not restrict traffic that ingresses and egresses the management interface, this is a finding.

Check Text ( C-77911r1_chk )

Step 1: Verify that the managed interface has an inbound and outbound ACL configured.

Step 2: Verify that the ingress ACL blocks all transit traffic—that is, any traffic not destined to the router itself. In addition, traffic accessing the managed router should be originated at the NOC.

Note that the destination used by any host within the management network to access the managed router must be via the management interface. The loopback should not be a valid address since these prefixes would not be advertised into the management network IGP domain. This could only be possible if the managed network elements had an IGP adjacency with the managed network, which should not be the case.

Step 3: Verify that the egress ACL blocks any traffic not originated by the managed router. In addition, traffic egressing the management interface must be destined to the NOC.

Caveat: This requirement is only applicable if the management interface connected to the OOBM access switch is a routed interface. If the management interface is a true OOBM interface, this requirement is not applicable.

If the router does not restrict traffic that ingresses and egresses the management interface, this is a finding.

Fix Text (F-85081r1_fix)
If the management interface is a routed interface, it must be configured with both an ingress and egress ACL. The ingress ACL should block any transit traffic, while the egress ACL should block any traffic that was not originated by the managed network device.