Detections
Analytics

CISC-RT-000830 - The Cisco multicast Rendezvous Point (RP) router must be configured to filter Protocol Independent Multicast (PIM) Register messages received from the Designated Router (DR) for any undesirable multicast groups and sources.

Information

Real-time multicast traffic can entail multiple large flows of data. An attacker can flood a network segment with multicast packets, over-using the available bandwidth and thereby creating a denial-of-service (DoS) condition. Hence, it is imperative that register messages are accepted only for authorized multicast groups and sources.

Solution

Configure the router to filter PIM register messages received from a multicast DR for any undesirable multicast groups and sources. The example below will deny any multicast streams for groups 239.5.0.0/16 and allow from only sources 10.1.2.6 and 10.1.2.7.

RP/0/0/CPU0:R2(config)#ipv4 access-list PIM_REGISTER_FILTER
RP/0/0/CPU0:R2(config-ipv4-acl)#deny ipv4 any 239.5.0.0 0.0.255.255
RP/0/0/CPU0:R2(config-ipv4-acl)#permit ipv4 host 10.1.2.6 any
RP/0/0/CPU0:R2(config-ipv4-acl)#permit ipv4 host 10.1.2.7 any
RP/0/0/CPU0:R2(config-ipv4-acl)#deny ipv4 any any
RP/0/0/CPU0:R2(config-ipv4-acl)#exit
RP/0/0/CPU0:R2(config)#router pim
RP/0/0/CPU0:R2(config-pim)#address-family ipv4
RP/0/0/CPU0:R2(config-pim-default-ipv4)#accept-register PIM_REGISTER_FILTER
RP/0/0/CPU0:R2(config-pim-default-ipv4)#end

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Cisco_IOS-XR_Router_Y26M01_STIG.zip

Item Details

Category: ACCESS CONTROL

References: 800-53|AC-4, CAT|III, CCI|CCI-001414, Rule-ID|SV-216811r1117237_rule, STIG-ID|CISC-RT-000830, STIG-Legacy|SV-105967, STIG-Legacy|V-96829, Vuln-ID|V-216811

Plugin: Cisco

Control ID: fcd4c4b50ece6f1160bd986a17c9961f3a096ce7b00922abfcdac951089d2ba6