Detections
Analytics
1.35 CISC-RT-000540
Information
The Cisco BGP switch must be configured to reject route advertisements from BGP peers that do not list their autonomous system (AS) number as the first AS in the AS_PATH attribute.GROUP ID: V-221108
RULE ID: SV-221108r999717
Verifying the path a route has traversed will ensure the IP core is not used as a transit network for unauthorized or possibly even internet traffic. All autonomous system boundary switches (ASBRs) must ensure updates received from eBGP peers list their AS number as the first AS in the AS_PATH attribute.
Solution
Configure the switch to deny updates received from eBGP peers that do not list their AS number as the first AS in the AS_PATH attribute.SW1(config)# router bgp xx
SW1(config-router)# enforce-first-as
SW1(config-router)# end
See Also
Item Details
Audit Name: CIS Cisco NX OS Switch RTR STIG v1.1.0 CAT III
Category: ACCESS CONTROL, SECURITY ASSESSMENT AND AUTHORIZATION, SYSTEM AND COMMUNICATIONS PROTECTION
References: 800-53|AC-4(8), 800-53|CA-7, 800-53|SC-4, CCI|CCI-000032, CSCv7|13.3, Rule-ID|SV-221108r999717_rule, STIG-ID|CISC-RT-000540, Vuln-ID|V-221108
Plugin: Cisco
Control ID: 0e55535fbfdeee6c929f755123cd956e5acb39ad4b2360296aea7c8eb91082fe