I'm looking to setup an integration between GitHub and Service Now and I can use OAuth2 using JWT Tokens, the steps to take can be found here.
There is a specific step that states:
Create a CA signed certificate using the GitHub App private key
I've followed the steps and a self-signed certificate is created based on the private key. This private key is used by Service Now to sign JWT tokens. I believe technically you could use this private key to create a CSR and use this to get a 3rd party CA signed certificate, but the question would be is there any benefit of this?
I don't believe there is any benefit as GitHub only stores the associated public key to verify that the JWT token has been signed by the respective private key.