STIGQter: STIG Summary: Arista MLS EOS 4.X Router Security Technical Implementation Guide Version: 2 Release: 2 Benchmark Date: 02 Apr 2025:

The MPLS router must be configured to use its loopback address as the source address for LDP peering sessions.

DISA Rule

SV-256049r991790_rule

Vulnerability Number

V-256049

Group Title

SRG-NET-000512-RTR-000002

Rule Version

ARST-RT-000700

Severity

CAT III

CCI(s)

• CCI-004931 - Establish organization-defined alternate communications paths for system operations organizational command and control.

Weight

10

Fix Recommendation

Configure the Arista MPLS routers to use their loopback address as the source address for LDP peering sessions.

Step 1: Configure the loopback interface.

LEAF-1A(config)#interface Loopback0
LEAF-1A(config-if-Lo0)#ip address 10.1.1.1/32

Step 2: Configure the loopback interface as LDP router-id.

LEAF-1A(config)#mpls ldp
LEAF-1A(config-mpls-ldp)#router-id interface Loopback0
LEAF-1A(config-mpls-ldp)#no shutdown

Check Contents

Review the Arista router configuration to determine if it uses its loopback address as the source address for LDP peering sessions.

To verify a loopback address has been configured as shown in the following example, execute the command "sh run int loopback YY".

interface loopback 0
ip address 10.1.1.1/32

An MPLS router will use the LDP router ID as the source address for LDP hellos and when establishing TCP sessions with LDP peers; hence, it is necessary to verify the LDP router ID is the same as the loopback address. By default, routers will assign the LDP router ID using the highest IP address on the router, with preference given to loopback addresses. If the router-id command is specified that overrides this default behavior, verify it is the IP address of the designated loopback interface.

mpls ldp
router-id interface Loopback0
no shutdown

If the Arista router is not configured to use its loopback address for LDP peering, this is a finding.

Vulnerability Number

V-256049

Documentable

False

Rule Version

ARST-RT-000700

Severity Override Guidance

Review the Arista router configuration to determine if it uses its loopback address as the source address for LDP peering sessions.

To verify a loopback address has been configured as shown in the following example, execute the command "sh run int loopback YY".

interface loopback 0
ip address 10.1.1.1/32

An MPLS router will use the LDP router ID as the source address for LDP hellos and when establishing TCP sessions with LDP peers; hence, it is necessary to verify the LDP router ID is the same as the loopback address. By default, routers will assign the LDP router ID using the highest IP address on the router, with preference given to loopback addresses. If the router-id command is specified that overrides this default behavior, verify it is the IP address of the designated loopback interface.

mpls ldp
router-id interface Loopback0
no shutdown

If the Arista router is not configured to use its loopback address for LDP peering, this is a finding.

Check Content Reference

M

Target Key

5513