The PE router must be configured to have each Virtual Routing and Forwarding (VRF) instance bound to the appropriate physical or logical interfaces to maintain traffic separation between all MPLS L3VPNs.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-256052	ARST-RT-000730	SV-256052r882498_rule		High

Description
The primary security model for an MPLS L3VPN infrastructure is traffic separation. The service provider must guarantee the customer that traffic from one VPN does not leak into another VPN or into the core, and that core traffic must not leak into any VPN. Hence, it is imperative that each CE-facing interface can only be associated to one VRF—that alone is the fundamental framework for traffic separation.

Description

The primary security model for an MPLS L3VPN infrastructure is traffic separation. The service provider must guarantee the customer that traffic from one VPN does not leak into another VPN or into the core, and that core traffic must not leak into any VPN. Hence, it is imperative that each CE-facing interface can only be associated to one VRF—that alone is the fundamental framework for traffic separation.

STIG	Date
Arista MLS EOS 4.2x Router Security Technical Implementation Guide	2023-01-17

Details

Check Text ( C-59728r882496_chk )
Review the design plan for deploying L3VPN and VRF-lite. Review all CE-facing interfaces and verify the proper VRF is defined. To verify the interfaces toward CE facing with proper VRF defined, execute the command "sh run int ethernet YY". vrf instance PROD vrf instance DEVP ip routing vrf PROD ip routing vrf DEVP interface Ethernet3 no routerport vrf PROD ip address 10.1.99.11/24 interface Ethernet4 no routerport vrf DEVP ip address 10.11.5.11/24 If any VRFs are not bound to the appropriate physical or logical interface, this is a finding.

Check Text ( C-59728r882496_chk )

Review the design plan for deploying L3VPN and VRF-lite.

Review all CE-facing interfaces and verify the proper VRF is defined.

To verify the interfaces toward CE facing with proper VRF defined, execute the command "sh run int ethernet YY".

vrf instance PROD
vrf instance DEVP

ip routing vrf PROD
ip routing vrf DEVP

interface Ethernet3
no routerport
vrf PROD
ip address 10.1.99.11/24

interface Ethernet4
no routerport
vrf DEVP
ip address 10.11.5.11/24

If any VRFs are not bound to the appropriate physical or logical interface, this is a finding.

Fix Text (F-59671r882497_fix)
Configure the Arista PE router to have each VRF bound to the appropriate physical or logical interfaces to maintain traffic separation between all MPLS L3VPNs. Configure the VRF on the CE facing interfaces. PE11(config)#vrf instance PROD PE11(config)#vrf instance DEVP ! PE11(config)#ip routing vrf PROD PE11(config)#ip routing vrf DEVP ! PE11(config)#interface Ethernet3 PE11(config-if-Et3)#no routerport PE11(config-if-Et3)#vrf PROD PE11(config-if-Et3)#ip address 10.1.99.11/24 ! PE11(config)#interface Ethernet4 PE11(config-if-Et3)#no routerport PE11(config-if-Et3)#vrf DEVP PE11(config-if-Et3)#ip address 10.11.5.11/24

Fix Text (F-59671r882497_fix)

Configure the Arista PE router to have each VRF bound to the appropriate physical or logical interfaces to maintain traffic separation between all MPLS L3VPNs.

Configure the VRF on the CE facing interfaces.

PE11(config)#vrf instance PROD
PE11(config)#vrf instance DEVP
!
PE11(config)#ip routing vrf PROD
PE11(config)#ip routing vrf DEVP
!
PE11(config)#interface Ethernet3
PE11(config-if-Et3)#no routerport
PE11(config-if-Et3)#vrf PROD
PE11(config-if-Et3)#ip address 10.1.99.11/24
!
PE11(config)#interface Ethernet4
PE11(config-if-Et3)#no routerport
PE11(config-if-Et3)#vrf DEVP
PE11(config-if-Et3)#ip address 10.11.5.11/24