Check: ARST-RT-000130
Arista MLS EOS 4.2x Router STIG:
ARST-RT-000130
(in version v1 r1)
Title
The Arista multicast router must be configured to bind a Protocol Independent Multicast (PIM) neighbor filter to interfaces that have PIM enabled. (Cat II impact)
Discussion
PIM is a routing protocol used to build multicast distribution trees for forwarding multicast traffic across the network infrastructure. PIM traffic must be limited to only known PIM neighbors by configuring and binding a PIM neighbor filter to those interfaces that have PIM enabled. If a PIM neighbor filter is not applied to those interfaces that have PIM enabled, unauthorized routers can join the PIM domain, discover and use the rendezvous points, and also advertise their rendezvous points into the domain. This can result in a denial of service by traffic flooding or result in the unauthorized transfer of data.
Check Content
This requirement is not applicable for the DODIN backbone. Review the Arista router multicast topology diagram and determine if router interfaces are enabled for IPv4 or IPv6 multicast routing. If the router is enabled for multicast routing, verify all interfaces enabled for PIM have a neighbor filter bound to the interface. The neighbor filter must only accept PIM control plane traffic from the documented PIM neighbors. Step 1: Verify the ACL is configured that will specify the authorized PIM neighbors. To verify IP access lists are configured, execute the command "show ip access-lists". ip access-list standard filter_1 permit 10.13.24.9/24 exit Step 2: Verify the PIM neighbor-filter is configured on PIM-enabled interfaces. To verify interfaces are configured, execute the command "show run int YY". interface vlan 4 pim ipv4 sparse-mode pim ipv4 neighbor-filter filter_1 exit If PIM neighbor filters are not bound to all interfaces that have PIM enabled, this is a finding.
Fix Text
This requirement is not applicable for the DODIN backbone. Configure neighbor filters to only accept PIM control plane traffic from documented PIM neighbors. Bind neighbor filters to all PIM-enabled interfaces. Step 1: Configure an ACL that will specify the authorized PIM neighbors. router(config)#ip access-list standard filter_1 router(config-std-acl-filter_1)#permit 10.13.24.9/24 router(config-std-acl-filter_1)#exit Step 2: Configure a PIM neighbor-filter command and apply it on all PIM-enabled interfaces that are referencing the PIM neighbor ACL. router(config)#interface vlan 4 router(config-if-Vl4)#pim ipv4 neighbor-filter filter_1 router(config-if-Vl4)#exit
Additional Identifiers
Rule ID: SV-255999r882339_rule
Vulnerability ID: V-255999
Group Title: SRG-NET-000019-RTR-000004
Expert Comments
CCIs
Number | Definition |
---|---|
CCI-001414 |
The information system enforces approved authorizations for controlling the flow of information between interconnected systems based on organization-defined information flow control policies. |
Controls
Number | Title |
---|---|
AC-4 |
Information Flow Enforcement |