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V-216614

CAT II (Medium)

The Cisco PE router providing MPLS Layer 2 Virtual Private Network (L2VPN) services must be configured to authenticate targeted Label Distribution Protocol (LDP) sessions used to exchange virtual circuit (VC) information using a FIPS-approved message authentication code algorithm.

Rule ID

SV-216614r864155_rule

STIG

Cisco IOS Router RTR Security Technical Implementation Guide

Version

V3R4

CCIs

CCI-001958

Discussion

LDP provides the signaling required for setting up and tearing down pseudowires (virtual circuits used to transport Layer 2 frames) across an MPLS IP core network. Using a targeted LDP session, each PE router advertises a virtual circuit label mapping that is used as part of the label stack imposed on the frames by the ingress PE router during packet forwarding. Authentication provides protection against spoofed TCP segments that can be introduced into the LDP sessions.

Check Content

The Cisco router is not compliant with this requirement; hence, it is a finding. However, the severity level can be mitigated to a category 3 if the router is configured to authenticate targeted LDP sessions using MD5 as shown in the configuration example below.

mpls ldp neighbor 10.1.1.2 password xxxxxxx
mpls label protocol ldp

If the router is not configured to authenticate targeted LDP sessions using MD5, the finding will remain as a category 2.

Fix Text

The severity level can be downgraded to a category 3 if the router is configured to authenticate targeted LDP sessions using MD5 as shown in the example below.

R5(config)#mpls ldp neighbor 10.1.1.2 password xxxxxxxx