Title

The Juniper Multicast Source Discovery Protocol (MSDP) router must be configured to use its loopback address as the source address when originating MSDP traffic. (Cat III impact)

Discussion

Using a loopback address as the source address offers a multitude of uses for security, access, management, and scalability of MSDP routers. It is easier to construct appropriate ingress filters for router management plane traffic destined to the network management subnet since the source addresses will be from the range used for loopback interfaces instead of a larger range of addresses used for physical interfaces. Log information recorded by authentication and syslog servers will record the router’s loopback address instead of the numerous physical interface addresses.

Check Content

Review the router configuration to verify that a loopback address has been configured. interfaces { … … … lo0 { unit 0 { family inet { address 2.2.2.2/32; } } } } Verify that the loopback interface is used as the source address for all MSDP packets generated by the router. protocols { msdp { group AS25 { peer 5.5.5.5 { local-address 2.2.2.2; } } } If the router does not use its loopback address as the source address when originating MSDP traffic, this is a finding.

Fix Text

Configure the router to use its loopback address is used as the source address when sending MSDP packets. [edit protocols msdp] set group AS_5 peer 5.5.5.5 local-address 2.2.2.2

Additional Identifiers

Rule ID: SV-217098r992008_rule

Vulnerability ID: V-217098

Group Title: SRG-NET-000512-RTR-000011

Expert Comments

CCIs tied to check.

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