This action will code sign files from the given folder, this can be done recursively if needed.
The action uses a base64 encoded PFX certificate to sign files by adding the certificate to the store and then use signtool to do the code signing.

All inputs regarding the Certificate except description should be added via repository/organization secrets.

Thanks to Dirk Lemstra for providing a base for me to create this action.

Required
Description - The base64 encoded certificate.

Required
Description - Certificate Password. Used to add to the machine store.

Required
Description - SHA1 hash for the certificate (Thumbprint of the certificate).

Description - Add a desciption to the files being signed.

Required
Description - The folder that contains the libraries to sign.

Description - Recursively search for DLL files.
Default - 'false'

Description - Url of the timestamp server.
Default - 'http://timestamp.verisign.com/scripts/timstamp.dll'

runs-on: windows-latest
steps:
  uses: GabrielAcostaEngler/signtool-code-sign@master
  with:
    certificate: '${{ secrets.CERTIFICATE }}'
    cert-password: '${{ secrets.PASSWORD }}'
    cert-sha1: '${{ secrets.CERTHASH }}'
    cert-description: 'foo'
    folder: 'path/to/folder'
    recursive: true
    timestamp-server: 'http://timestamp.digicert.com'

This project is released under the MIT License