The Cisco perimeter router must be configured to not be a Border Gateway Protocol (BGP) peer to an alternate gateway service provider.
An XCCDF Rule
Description
<VulnDiscussion>ISPs use BGP to share route information with other autonomous systems (i.e. other ISPs and corporate networks). If the perimeter router was configured to BGP peer with an ISP, NIPRnet routes could be advertised to the ISP, thereby creating a backdoor connection from the Internet to the NIPRnet.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-216667r531086_rule
- Severity
- High
- References
- Updated
Remediation - Manual Procedure
This requirement is not applicable for the DODIN Backbone.
Remove any BGP neighbors belonging to the alternate gateway service provider and configure a static route to forward Internet bound traffic to the alternate gateway as shown in the example below:
R5(config)#ip route 0.0.0.0 0.0.0.0 x.22.1.14