AOS, when used as a VPN Gateway, must authenticate all network-connected endpoint devices before establishing a connection.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-266988	SRG-NET-000343-VPN-001370	ARBA-VN-001370	SV-266988r1040893_rule	2024-10-29	1

Description
Without authenticating devices, unidentified or unknown devices may be introduced, thereby facilitating malicious activity. For distributed architectures (e.g., service-oriented architectures), the decisions regarding the validation of authentication claims may be made by services separate from the services acting on those decisions. In such situations, it is necessary to provide authentication decisions (as opposed to the actual authenticators) to the services that need to act on those decisions. This requirement applies to applications that connect either locally, remotely, or through a network to an endpoint device (including, but not limited to, workstations, printers, servers (outside a datacenter), VoIP Phones, and VTC codecs). Gateways and SOA applications are examples of where this requirement would apply. Device authentication is a solution enabling an organization to manage devices. It is an additional layer of authentication ensuring only specific preauthorized devices can access the system.

Description

Without authenticating devices, unidentified or unknown devices may be introduced, thereby facilitating malicious activity. For distributed architectures (e.g., service-oriented architectures), the decisions regarding the validation of authentication claims may be made by services separate from the services acting on those decisions. In such situations, it is necessary to provide authentication decisions (as opposed to the actual authenticators) to the services that need to act on those decisions. This requirement applies to applications that connect either locally, remotely, or through a network to an endpoint device (including, but not limited to, workstations, printers, servers (outside a datacenter), VoIP Phones, and VTC codecs). Gateways and SOA applications are examples of where this requirement would apply. Device authentication is a solution enabling an organization to manage devices. It is an additional layer of authentication ensuring only specific preauthorized devices can access the system.

ℹ️ Check
Verify the AOS configuration with the following command: 1. Site-to-site VPN: Using the CLI: show crypto isakmp sa If the IPsec security association is not operating with certificates ("-c"), this is a finding. 2. Hardware client VPN: Using the web GUI, navigate to Configuration >> Access Points >> Remote APs. Review each provisioned RAP and verify that each AP has "c" in the FLAGS column. If certificate authentication is not configured for each RAP, this is a finding.

ℹ️ Check

Verify the AOS configuration with the following command: 1. Site-to-site VPN: Using the CLI: show crypto isakmp sa If the IPsec security association is not operating with certificates ("-c"), this is a finding. 2. Hardware client VPN: Using the web GUI, navigate to Configuration >> Access Points >> Remote APs. Review each provisioned RAP and verify that each AP has "c" in the FLAGS column. If certificate authentication is not configured for each RAP, this is a finding.

✔️ Fix
Configure AOS using the web interface: 1. Navigate to Configuration >> Services >> VPN and expand "Site-to-Site". 2. Select the configured site-to-site VPN IPsec maps. Select the applicable Server certificate. Select the applicable trusted DOD root CA under "CA certificate:". 3. Click Submit >> Pending Changes >> Deploy Changes. 4. Navigate to Configuration >> Access Points >> Remote APs tab. 5. Select the check box next to the AP Name in the Remote AP table and click "Provision". 6. In the "General" tab, select "Certificate" from the "Authentication method:" drop-down list. 7. Click "Submit" to apply the configuration and reboot the AP as a certificate Remote AP. 8. Click Pending Changes >> Deploy Changes.

✔️ Fix

Configure AOS using the web interface: 1. Navigate to Configuration >> Services >> VPN and expand "Site-to-Site". 2. Select the configured site-to-site VPN IPsec maps. Select the applicable Server certificate. Select the applicable trusted DOD root CA under "CA certificate:". 3. Click Submit >> Pending Changes >> Deploy Changes. 4. Navigate to Configuration >> Access Points >> Remote APs tab. 5. Select the check box next to the AP Name in the Remote AP table and click "Provision". 6. In the "General" tab, select "Certificate" from the "Authentication method:" drop-down list. 7. Click "Submit" to apply the configuration and reboot the AP as a certificate Remote AP. 8. Click Pending Changes >> Deploy Changes.