Hi, for our company i need to find the cvmp number for stunnel however I am not able to find it.

Is there anyone who can help me with that?

https://csrc.nist.gov/projects/cryptographic-module-validation-program/validated-modules/search/all

I could not find stunnel here.

No surprise here.  As mentioned on https://www.stunnel.org/, stunnel uses a cryptographic module for OpenSSL, which is a separate product.

You can use one of the following validated modules: https://csrc.nist.gov/projects/cryptographic-module-validation-program/validated-modules/search?SearchMode=Basic&ModuleName=openssl&CertificateStatus=Active&ValidationYear=0

The one I distribute with my Windows build is https://csrc.nist.gov/projects/cryptographic-module-validation-program/certificate/4282

Best regards,
    Mike