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V-273576

CAT III (Low)

The RUCKUS ICX Multicast Source Discovery Protocol router must be configured to filter source-active multicast advertisements to external MSDP peers to avoid global visibility of local-only multicast sources and groups.

Rule ID

SV-273576r1110885_rule

STIG

RUCKUS ICX Router Security Technical Implementation Guide

Version

V1R1

CCIs

CCI-001368

Discussion

To avoid global visibility of local information, there are a number of source-group (S, G) states in a PIM-SM domain that must not be leaked to another domain, such as multicast sources with private address, administratively scoped multicast addresses, and the auto-RP groups (224.0.1.39 and 224.0.1.40). Allowing a multicast distribution tree, local to the core, to extend beyond its boundary could enable local multicast traffic to leak into other autonomous systems and customer networks.

Check Content

Check for SA filter on MSDP peer:

ICX#  show msdp peer x.x.x.x | include Output 

        Output SA Filter:Applicable
        Output (S,G) route-map:out_MSDP_SA_filter
        Output RP route-map:None

If any configured MSDP peer is not configured to filter outbound advertisements to avoid local-only multicast sources and groups, this is a finding.

Fix Text

Create access list to filter source-active multicast advertisements for any undesirable multicast groups and sources:

ip access-list extended out_MSDP_SA_filter
 sequence 10 deny ip 10.0.0.0/8 any
 sequence 20 permit ip any any

route-map out_MSDP_SA_filter permit 10
 match ip address out_MSDP_SA_filter

router msdp
 msdp-peer x.x.x.x
 sa-filter originate route-map out_MSDP_SA_filter
!