Installing Root Certificate

Execution

Adding a certificate with a native windows binary:

certutil.exe -addstore -f -user Root C:\Users\spot\Downloads\certnew.cer

Checking to see the certificate got installed:

Adding the certificate with powershell:

Import-Certificate -FilePath C:\Users\spot\Downloads\certnew.cer -CertStoreLocation Cert:\CurrentUser\Root\

Observations

Advanced poweshell logging to the rescue:

Commandline logging:

The CAs get installed to:

Computer\HKEY_CURRENT_USER\Software\Microsoft\SystemCertificates\Root\Certificates\C6B22A75B0633E76C9F21A81F2EE6E991F5C94AE

..so it is worth monitoring registry changes there:

References

Subvert Trust Controls: Install Root Certificate, Sub-technique T1553.004 - Enterprise | MITRE ATT&CK®