How to create a certificate and use it to self sign PowerShell scripts

PS_SelfSign_PS_Scripts.md

Create a new personal certificate

• $certificateName = Read-Host -Prompt 'Enter name of your certificate e.g. MyCert or [email protected]'
• $cert = New-SelfSignedCertificate -DnsName $certificateName -CertStoreLocation Cert:\CurrentUser\My\ -Type Codesigning -NotAfter (Get-Date).AddYears(3)

Or get an already-created personal certificate

• $certThumprint = Read-Host -Prompt 'Enter thumbprint of your certificate'
• $cert = Get-ChildItem -Path Cert:\CurrentUser\My\ | Where { $_.Thumbprint -eq $certThumprint }

Import the created certificate into Trusted Publishers and Trusted Root Certification Authorities

This can be done manually using certmgr.msc or using the following commands:

• Export your certificate into a .cer file
  • Export-Certificate -Type CERT -Cert $cert -FilePath $env:userprofile\documents\myCert.cer
  • Import-Certificate -FilePath $env:userprofile\documents\myCert.cer -CertStoreLocation Cert:\CurrentUser\TrustedPublisher
  • Import-Certificate -FilePath $env:userprofile\documents\myCert.cer -CertStoreLocation Cert:\CurrentUser\Root -Confirm

Sign your PowerShell script (.ps1) file

• $pathToPs1File=Read-Host -Prompt 'Enter path to your ps1 script'
• Set-AuthenticodeSignature -FilePath $pathToPs1File -Certificate $cert