All Signed PowerShell Execution Policy

Purpose

You receive an error when running a PowerShell script or command from PDQ Deploy or PDQ Inventory similar to:

You cannot run this script on the current system. For more information about running scripts and setting execution policy, see about_Execution_Policies at http://go.microsoft.com/fwlink/?LinkID=135170.

From Error Handling Wrapper.ps1 

If you encounter an error similar to this when attempting to run a PowerShell script that did not come from PDQ.com, see this article about Signing Your PowerShell Scripts.

Resolution

PDQ.com signs each of our .ps1 files included in the product; this includes the error handling wrapper script that is used when executing PowerShell steps or remote commands, as well as any .ps1 in the package library with a code-signing certificate issued by Digicert. Any .ps1 file that is not provided directly from PDQ.com is not, and cannot be signed with this certificate. This includes any PowerShell directly entered into a PowerShell step, or PowerShell tool, but there is a workaround listed below to sign these yourself. If your organization requires all scripts to be signed, it is recommended to use an install step with a signed .ps1 as the installer file.

The thumbprint of the cert is:

PDQ Deploy and Inventory version 18.1.28.0 and later:
32AE19914C02705091C58368406293D642F39516

Before version 18.1.28.0:
709DF96FEEDE2CAB2A5FB803BEB599571D18A1D4

CN=PDQ.COM CORPORATION, O=PDQ.COM CORPORATION, L=Salt Lake City, S=Utah, C=US

This certificate is not included in the Trusted Publishers on Windows by default. This is the same code signing certificate with which we sign our applications. When the execution policy of "All-Signed" is set, this will only run scripts when the entire cert chain is installed and trusted. Conversely, installing a signed application does not have this requirement; the installed application must only have a valid signature.

In order to run a PowerShell script from our product when the "All-Signed" execution policy is set, you will need to install the certificate chain. There are a few of ways to accomplish this on your remote machines. First, we must extract the certificate from the product itself. The below PowerShell command will export a .cer file that you can deploy in whichever manner you chose:

Defining the code-signing certificate as a variable

$cert = (Get-AuthenticodeSignature -FilePath "C:\Program Files (x86)\Admin Arsenal\PDQ Deploy\PDQDeployConsole.exe").SignerCertificate

Exporting the certificate to a file

Export-Certificate -Cert $cert -Filepath C:\pdqcert.cer -Type Cert

Now that we have the certificate exported, we have a couple options on how to install this certificate:

1. Group Policy - https://docs.microsoft.com/en-us/windows-server/identity/ad-fs/deployment/distribute-certificates-to-client-computers-by-using-group-policy

2. PowerShell - Importing the certificate created previously to the computer Trusted Publishers store.

Import-Certificate -Filepath C:\pdqcert.cer -CertStoreLocation Cert:\LocalMachine\TrustedPublisher\

Signing PowerShell Steps and Tools

When using a PowerShell step or a PowerShell tool, there are are scripts generated from the contents of these windows that are not signed unless the signature block is included. This signature block may be copied and pasted in after signing a script using the method described in Signing Your PowerShell Scripts.

A user.ps1 script is generated from the contents of a PowerShell step window. The below screenshot shows where you would need to paste the signature block in order to subsequently sign user.ps1.

A command.ps1 script is generated from the contents of a PowerShell tool window. The below screenshot shows where you would need to paste the signature block in order to subsequently sign command.ps1.

See Also

Article - Signing Your PowerShell Scripts

Article - Install a Certificate to the Trusted Root Certificate Authorities