Title

The Juniper PE router must be configured to have each Virtual Routing and Forwarding (VRF) instance with the appropriate Route Target (RT). (Cat I impact)

Discussion

The primary security model for an MPLS L3VPN as well as a VRF-lite infrastructure is traffic separation. Each interface can only be associated to one VRF, which is the fundamental framework for traffic separation. Forwarding decisions are made based on the routing table belonging to the VRF. Control of what routes are imported into or exported from a VRF is based on the RT. It is critical that traffic does not leak from one COI tenant or L3VPN to another; hence, it is imperative that the correct RT is configured for each VRF.

Check Content

Verify that the correct RT is configured for each VRF. Review the design plan for MPLS/L3VPN and VRF-lite to determine what RTs have been assigned for each VRF. Review the route-distinguisher and vrf-target statements under each configured VRF and verify that the correct RTs have been defined for each VRF. Assuming the assigned RT for "customer 1" is "cust1:33:33", verify vrf-target matches. [edit routing-instances] <instance name> { description "To customer 1"; instance-type vrf; interface <ce-facing interface>.<logical unit>; route-distinguisher 33:33; << Must match the design plan for "customer 1". vrf-target cust1:33:33; << Must match the design plan for "customer 1". vrf-table-label; protocols { ospf { area <number> { interface <ce-facing interface>.<logical unit>; } } } } Note: In L3 VPN, the CE router forms an adjacency with the PE router (OSPF in the example). If there are VRFs configured with the wrong RT, this is a finding.

Fix Text

Configure all J-PE routers to have the correct VRF defined with the appropriate RT. set routing-instances <name> description <"appropriate description"> set routing-instances <name> instance-type vrf set routing-instances <name> interface <ce-facing interface>.<logical unit> set routing-instances <name> route-distinguisher 33:33 << Must match the design plan for "customer 1". set routing-instances <name> vrf-target cust1:33:33 << Must match the design plan for "customer 1". set routing-instances <name> vrf-table-label set routing-instances <name> protocols ospf area <number> interface <ce-facing interface>.<logical unit>

Additional Identifiers

Rule ID: SV-254065r844228_rule

Vulnerability ID: V-254065

Group Title: SRG-NET-000512-RTR-000006

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.