Check: SRG-NET-000018-RTR-000003
Router SRG:
SRG-NET-000018-RTR-000003
(in versions v4 r3 through v4 r1)
Title
The BGP router must be configured to reject inbound route advertisements for any prefixes belonging to the local autonomous system (AS). (Cat II impact)
Discussion
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.
Check Content
Review the router configuration to verify that it will reject routes belonging to the local AS. The prefix filter must be referenced inbound on the appropriate BGP neighbor statements. If the router is not configured to reject inbound route advertisements belonging to the local AS, this is a finding.
Fix Text
Ensure all eBGP routers are configured to reject inbound route advertisements for any prefixes belonging to the local AS.
Additional Identifiers
Rule ID: SV-207099r604135_rule
Vulnerability ID: V-207099
Group Title: SRG-NET-000018
Expert Comments
CCIs
| Number | Definition |
|---|---|
| CCI-001368 |
The information system enforces approved authorizations for controlling the flow of information within the system based on organization-defined information flow control policies. |
Controls
| Number | Title |
|---|---|
| AC-4 |
Information Flow Enforcement |