Check: AMLS-L3-000150
Arista MLS DCS-7000 Series RTR STIG:
AMLS-L3-000150
(in versions v1 r3 through v1 r2)
Title
The Arista Multilayer Switch must protect an enclave connected to an Alternate Gateway by using an inbound filter that only permits packets with destination addresses within the sites address space. (Cat II impact)
Discussion
Enclaves with Alternate Gateway connections must take additional steps to ensure there is no compromise on the enclave network or NIPRNet. Without verifying the destination address of traffic coming from the site's Alternate Gateway, the perimeter router could be routing transit data from the Internet into the NIPRNet. This could also make the perimeter router vulnerable to a DoS attack as well as provide a backdoor into the NIPRNet. The DoD enclave must ensure the ingress filter applied to external interfaces on a perimeter router connecting to an Approved Gateway is secure through filters permitting packets with a destination address belonging to the DoD enclave's address block.
Check Content
Review the configuration of each router interface connecting to an Alternate Gateway via the "show running-config" command. Verify each permit statement of the ingress filter only permits packets with destination addresses of the site's NIPRNet address space or a destination address belonging to the address block assigned by the Alternate Gateway network service provider. If the ingress filter permits packets with addresses other than those specified, such as destination addresses of the site's NIPRNet address space or a destination address belonging to the address block assigned by the Alternate Gateway network service provider, this is a finding.
Fix Text
Configure the ingress filter of the perimeter router connected to an Alternate Gateway to only permit packets with destination addresses of the site's NIPRNet address space or a destination address belonging to the address block assigned by the Alternate Gateway network service provider. To configure an example of such a statement, enter: ip access-list [name] permit ip [source] [destination] exit interface [router interface] ip access-group [name] in exit
Additional Identifiers
Rule ID: SV-75355r1_rule
Vulnerability ID: V-60897
Group Title: SRG-NET-000019-RTR-000009
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 |