The Cisco BGP router must be configured to reject inbound route advertisements for any prefixes belonging to the local autonomous system (AS).
An XCCDF Rule
Description
<VulnDiscussion>Accepting route advertisements belonging to the local AS can result in traffic looping or being black holed, or at a minimum using a non-optimized path.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-216778r531087_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Step 1: Configure a prefix set containing the current Bogon prefixes as shown below.
RP/0/0/CPU0:R2(config)#prefix-set Step 1: Configure a prefix set containing the current Bogon prefixes as shown below.
RP/0/0/CPU0:R2(config)#prefix-set LOCAL_PREFIX
RP/0/0/CPU0:R2(config-pfx)#x.13.1.0/24 le 32