Vulnerability Discussion

To ensure users do not experience denial of service when performing certificate-based authentication to DOD websites due to the system chaining to a root other than DOD Root CAs, the DOD Interoperability Root CA cross-certificates must be installed in the Untrusted Certificate Store. This requirement only applies to unclassified systems.

Satisfies: SRG-OS-000066-GPOS-00034, SRG-OS-000403-GPOS-00182

Check

This is applicable to unclassified systems. It is not applicable for others.

Open PowerShell as an administrator.

Execute the following command:

Get-ChildItem -Path Cert:Localmachine\disallowed | Where {$_.Issuer -Like "*DOD Interoperability*" -and $_.Subject -Like "*DOD*"} | FL Subject, Issuer, Thumbprint, NotAfter

If the following certificate "Subject", "Issuer", and "Thumbprint" information is not displayed, this is a finding:

Subject: CN=DOD Root CA 3, OU=PKI, OU=DOD, O=U.S. Government, C=US
Issuer: CN=DOD Interoperability Root CA 2, OU=PKI, OU=DOD, O=U.S. Government, C=US
Thumbprint: AC06108CA348CC03B53795C64BF84403C1DBD341
NotAfter: 1/22/2025 10:22:56 AM

Subject: CN=DOD Root CA 2, OU=PKI, OU=DOD, O=U.S. Government, C=US
Issuer: CN=DOD Interoperability Root CA 1, OU=PKI, OU=DOD, O=U.S. Government, C=US
Thumbprint: A8C27332CCB4CA49554CE55D34062A7DD2850C02
NotAfter: 8/26/2025 9:25:51 AM

Alternately, use the Certificates MMC snap-in:

Run "MMC".

Select "File", "Add/Remove Snap-in".

Select "Certificates" and click "Add".

Select "Computer account" and click "Next".

Select "Local computer: (the computer this console is running on)" and click "Finish".

Click "OK".

Expand "Certificates" and navigate to Untrusted Certificates >> Certificates.

For each certificate with "DOD Root CA..." under "Issued To" and "DOD Interoperability Root CA..." under "Issued By":

Right-click the certificate and select "Open".

Select the "Details" tab.

Scroll to the bottom and select "Thumbprint".

If the certificates below are not listed or the value for the "Thumbprint" field is not as noted, this is a finding:

Issued To: DOD Root CA 3
Issued By: DOD Interoperability Root CA 2
Thumbprint: 49CBE933151872E17C8EAE7F0ABA97FB610F6477
Valid to: Wednesday, November 16, 2024

Issued To: DOD Root CA 3
Issued By: DOD Interoperability Root CA 2
Thumbprint: AC06108CA348CC03B53795C64BF84403C1DBD341
Valid to: Saturday, January 22, 2025

Fix

Install the DOD Interoperability Root CA cross-certificates on unclassified systems.

Issued To - Issued By - Thumbprint

DOD Root CA 3- DOD Interoperability Root CA 2 - 49CBE933151872E17C8EAE7F0ABA97FB610F6477

DOD Root CA 3 - DOD Interoperability Root CA 2 - AC06108CA348CC03B53795C64BF84403C1DBD341

Administrators must run the Federal Bridge Certification Authority (FBCA) Cross-Certificate Removal Tool once as an administrator and once as the current user.

The FBCA Cross-Certificate Remover Tool and User Guide are available on Cyber Exchange at https://cyber.mil/pki-pke/tools-configuration-files.