Detections
Analytics
CISC-RT-000900 - The Cisco Multicast Source Discovery Protocol (MSDP) router must be configured to only accept MSDP packets from known MSDP peers.
Information
MSDP peering with customer network routers presents additional risks to the DISN Core, whether from a rogue or misconfigured MSDP-enabled router.To guard against an attack from malicious MSDP traffic, the receive path or interface filter for all MSDP-enabled RP routers must be configured to only accept MSDP packets from known MSDP peers.
Solution
Configure the interface ACLs to only accept MSDP packets from known MSDP peers.RP/0/0/CPU0:R2(config)#ipv4 access-list EXTERNAL_ACL_INBOUND
RP/0/0/CPU0:R2(config-ipv4-acl)#permit tcp host x.1.28.2 host x.1.28.8 eq 639
RP/0/0/CPU0:R2(config-ipv4-acl)#deny tcp any host x.1.28.8 eq 639 log
RP/0/0/CPU0:R2(config-ipv4-acl)#permit tcp host x.1.28.2 host x.1.28.8 eq bgp
RP/0/0/CPU0:R2(config-ipv4-acl)#permit tcp host x.1.28.2 eq bgp host x.1.28.8
RP/0/0/CPU0:R2(config-ipv4-acl)#permit pim host x.1.28.2 host x.1.28.8
RP/0/0/CPU0:R2(config-ipv4-acl)#permit tcp any any established
...
...
...
RP/0/0/CPU0:R2(config-ipv4-acl)#deny ip any any log
See Also
https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Cisco_IOS-XR_Router_Y26M04_STIG.zip
Item Details
Audit Name: DISA Cisco IOS XR Router RTR STIG v3r3
Category: SYSTEM AND COMMUNICATIONS PROTECTION
References: 800-53|SC-7(11), CAT|II, CCI|CCI-002403, Rule-ID|SV-216818r856455_rule, STIG-ID|CISC-RT-000900, STIG-Legacy|SV-105981, STIG-Legacy|V-96843, Vuln-ID|V-216818
Plugin: Cisco
Control ID: f21c2cd3a99691198c08b673679527dcd63f5259b4152c816282ff7597469bb1