Dear Kerberos team,

Recently, we’ve faced the issue in our application that it can’t authenticate Windows server using NTLMSSP authentication method.

Our application is hosted on Alpine Docker image 3.20. There is a krb5-1.21.3-r0 package installed there.

Previously we’ve used Alpine 3.18 + krb5-1.20.2-r0 and it worked fine and still working fine.

Also there is gss-ntlmssp(https://github.com/gssapi/gss-ntlmssp) package that was built manually (since there is no such package for Alpine) and placed inside the Docker image.

Our application is just throwing error “Authentication validation failed with error - InvalidToken.”.

I’ve tested this on PowerShell as well and faced the same error: “Invoke-RestMethod: Authentication validation failed with error - InvalidToken.”

Do you have any resolution or maybe some pinpoints to get to resolution of it?

Thank you in advance.

Kind regards,

Yevhenii Lavrenchuk | Senior DevOps Engineer