How to return custom response from spring reactive application when the cors origin dosent match

Question

Implementing WebFluxConfigurer and override addCorsMapping and add the allowedOrigins, headers and methods.

Now if a request comes on the service and origin does not meet then it automatically gives 403 Forbidden, but I want to return custom error code let say 500

how to achieve this

what I am using: -spring reactive -webFlux

I have tried extending DefaultCorsProcessor but unable to make this work as not sure how to register it.