The Cisco BGP router must be configured to reject outbound route advertisements for any prefixes that do not belong to any customers or the local autonomous system (AS).
An XCCDF Rule
Description
<VulnDiscussion>Advertisement of routes by an autonomous system for networks that do not belong to any of its customers pulls traffic away from the authorized network. This causes a denial of service (DoS) on the network that allocated the block of addresses and may cause a DoS on the network that is inadvertently advertising it as the originator. It is also possible that a misconfigured or compromised router within the GIG IP core could redistribute IGP routes into BGP, thereby leaking internal routes.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-216780r531087_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
This requirement is not applicable for the DODIN Backbone.
Step 1: Configure a prefix set for customer and local autonomous system prefixes as shown in the example.
RP/0/0/CPU0:R2(config)#prefix-set CE_PREFIX_ADVERTISEMENTS
RP/0/0/CPU0:R2(config-pfx)#x.13.1.0/24 le 32,