ARST-RT-000020 - The Arista BGP router must be configured to reject inbound route advertisements for any Bogon prefixes.

Information

Accepting route advertisements for bogon prefixes can result in the local autonomous system (AS) becoming a transit for malicious traffic as it will in turn advertise these prefixes to neighbor autonomous systems.

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

Solution

Step 1: Configure the BGP Bogon Prefix List.

LEAF-1A(config)#ip prefix-list BOGON_v4
LEAF-1A(config-ip-pfx)#seq 1 deny 0.0.0.0/8 le 32
LEAF-1A(config-ip-pfx)#seq 2 deny 10.0.0.0/8 le 32
LEAF-1A(config-ip-pfx)#seq 3 deny 100.64.0.0/10 le 32
LEAF-1A(config-ip-pfx)#seq 4 deny 127.0.0.0/8 le 32
LEAF-1A(config-ip-pfx)#seq 5 deny 169.254.0.0/16 le 32
LEAF-1A(config-ip-pfx)#seq 6 deny 172.16.0.0/12 le 32
LEAF-1A(config-ip-pfx)#seq 100 permit 0.0.0.0/0 ge 8

Step 2: Configure the prefix list inbound to the appropriate BGP neighbor.

LEAF-1A(config)#router bgp 65001
LEAF-1A(config-router-bgp)#neighbor 100.2.1.1 prefix-list BOGON_v4 in

See Also

https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Arista_MLS_EOS_4-2x_Y23M02_STIG.zip

Item Details

Category: ACCESS CONTROL

References: 800-53|AC-4, CAT|II, CCI|CCI-001368, Rule-ID|SV-255988r882306_rule, STIG-ID|ARST-RT-000020, Vuln-ID|V-255988

Plugin: Arista

Control ID: 3866e55dd7fbd4af3e7b2376526398adfcb3bcc392abb7a68a6360a752a2e806