Detections
Analytics

ARST-RT-000660 - The Arista multicast Designated Router (DR) must be configured to filter the Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) Report messages to allow hosts to join only multicast groups that have been approved by the organization.

Information

Real-time multicast traffic can entail multiple large flows of data. Large unicast flows tend to be fairly isolated (i.e., someone doing a file download here or there), whereas multicast can have broader impact on bandwidth consumption, resulting in extreme network congestion. Hence, it is imperative that there is multicast admission control to restrict which multicast groups hosts are allowed to join via IGMP or MLD.

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

Solution

Configure the Arista DR to filter the IGMP and MLD report messages to allow hosts to join only multicast groups that have been approved.

Step 1: Configure the ACL to filter the unauthorized IGMP groups.

LEAF-1A(config-if-Et3)#ip access-list FILTER_IGMP
LEAF-1A(config-acl-FILTER_IGMP)# 10 deny igmp 232.0.0.0/8 any
LEAF-1A(config-acl-FILTER_IGMP)# 20 permit ip any any

Step 2: Configure the IGMP filter in IGMP process.

LEAF-1A(config-acl-FILTER_IGMP)#router igmp
LEAF-1A(config-router-igmp)# ip igmp access-group FILTER_IGMP

or

Configure the IGMP filter on internal host-facing interfaces (IGMP process) to filter IGMP.

LEAF-1A(config-router-igmp)#interface ethernet 3
LEAF-1A(config-if-Et3)# ip access-group FILTER_IGMP in

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Arista_MLS_EOS_4-X_Y25M07_STIG.zip

Item Details

Category: SYSTEM AND COMMUNICATIONS PROTECTION

References: 800-53|SC-7(11), CAT|III, CCI|CCI-002403, Rule-ID|SV-256045r882477_rule, STIG-ID|ARST-RT-000660, Vuln-ID|V-256045

Plugin: Arista

Control ID: f89afbec2342de1888abe1814ad142fedb4d975e818603e4af4d42746dc46c65