JUEX-RT-000070 - The Juniper router configured for Multicast Source Discovery Protocol (MSDP) must filter received source-active multicast advertisements for any undesirable multicast groups and sources.

Information

The interoperability of BGP extensions for interdomain multicast routing and MSDP enables seamless connectivity of multicast domains between autonomous systems. MP-BGP advertises the unicast prefixes of the multicast sources used by Protocol Independent Multicast (PIM) routers to perform RPF checks and build multicast distribution trees. MSDP is a mechanism used to connect multiple PIM sparse-mode domains, allowing RPs from different domains to share information about active sources. When RPs in peering multicast domains hear about active sources, they can pass on that information to their local receivers, thereby allowing multicast data to be forwarded between the domains. Configuring an import policy to block multicast advertisements for reserved, martian, single-source multicast, and any other undesirable multicast groups, as well as any source-group (S, G) states with Bogon source addresses, would assist in avoiding unwanted multicast traffic from traversing the core.

NOTE: Nessus has provided the target output to assist in reviewing the benchmark to ensure target compliance.

Solution

Configure the MSDP router to implement an import policy to block multicast advertisements for undesirable multicast groups and sources.

set protocols msdp peer <address> import source-active-filter

set policy-options policy-statement source-active-filter term unauth-groups from route-filter 224.0.1.2/32 exact
set policy-options policy-statement source-active-filter term unauth-groups from route-filter 224.0.2.2/32 exact
set policy-options policy-statement source-active-filter term unauth-groups then reject
set policy-options policy-statement source-active-filter term unauth-sources from source-address-filter 10.0.0.0/8 orlonger
set policy-options policy-statement source-active-filter term unauth-sources from source-address-filter 127.0.0.0/8 orlonger
set policy-options policy-statement source-active-filter term unauth-sources then reject

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Juniper_EX_Switches_Y24M01_STIG.zip

Item Details

Category: ACCESS CONTROL

References: 800-53|AC-4, CAT|III, CCI|CCI-001368, Rule-ID|SV-253979r843970_rule, STIG-ID|JUEX-RT-000070, Vuln-ID|V-253979

Plugin: Juniper

Control ID: 6b87efc46121aad7e6185ec3f58525951ec9db2f2908907b8a570e49121a55e6