[keycloak-user] Verification of Access Token failed

[Tim Rademacher]

Hi all,

 

I am struggling with access token verification.

 

So here is what I am doing (using Keycloak 4.5):

 

1.	Generate an offline auth code from Client A.
2.	Generate a refresh token from Client A.
3.	Generate an access token from Client A. This token has an *ES256*
Signatur.

 

When using this token, I got an error from my Spring Boot application, that
the used public key was not available: "Didn't find publicKey for specified
kid".

 

I set the public-key-cache-ttl to 1 sec and the log level to debug and could
see, that only one pubilc key was retrieved for my configured Client: "Realm
public keys successfully retrieved for client xxxxxxxxxx. New kids:
[xxxxx]".

 

As I could see in the realm settings, the key was created using *RS256*.

 

When I force the Client A to just use RS256 signature by setting the "Access
Token Signature Algorithm", then it works fine. But I wonder, how I could
also use other signature algorithms!? Release notes are stating, that both
(and more) algorithms are supported.

 

Thanks for your help!

 

Regards

 

Tim