Re: Hunting for the thumbprint for a cert on my IBMi

Hello,

Am 19.12.2025 um 23:31 schrieb smith5646midrange@xxxxxxxxx:

We installed a certificate on my IBMi that their software generated and I have been asked to provide the thumbprint. I did a google search on where to find the thumbprint and I did not find anything helpful.

The Thumbprint is the hash ("checksum") value of some data stored in some fields in the certificate, and easily obtained from certificates stored in Microsoft Windows certificate stores with the right mouse actions.

You could import the certificate into your local Windows store, and obtain the certificate's thumbprint(s) from there.

The pages would tell me to find and click options that are not on my screen.

Possibly different Windows versions?

The only thing that I can find close to what the internet says a thumbprint looks like is a serial number. Are they the same thing? Google seems to think that answer is no.

I don't know how exactly you've searched, but I easily found quite a lot of sources explaining what a thumbprint is. It's not a serial number, it's kind of a checksum.

https://en.wikipedia.org/wiki/Hash_function

Can anyone tell me how to find the thumbprint for this cert? It is running 7.3 so I can't ask IBM.

If you have installed the OpenSource tools, you can install and use OpenSSL on a shell command line. See here for an explanation of the procedure:

https://unix.stackexchange.com/questions/140601/verifying-a-ssl-certificates-fingerprint

In short: openssl x509 -in CERT.pem -noout -sha256 -fingerprint

Of course, the fingerprint will wildly differ with different hashing algorithms. So, there is no "the thumbprint", without stating which hashing algorithm should be used.

Does that help a bit?

:wq! PoC