org.springframework.security.AuthenticationCredentialsNotFoundException: An Authentication object was not found in the SecurityC

Reference:

1.5.

I get an exception with the message "An Authentication object was not found in the SecurityContext". What's wrong?

This is a another debug level message which occurs the first time an anonymous user attempts to access a protected resource, but when you do not have an AnonymousAuthenticationFilter in your filter chain configuration.
DEBUG [ExceptionTranslationFilter] - Authentication exception occurred; redirecting to authentication entry point
org.springframework.security.AuthenticationCredentialsNotFoundException:
An Authentication object was not found in the SecurityContext
at org.springframework.security.intercept.AbstractSecurityInterceptor.credentialsNotFound(AbstractSecurityInterceptor.java:342)
at org.springframework.security.intercept.AbstractSecurityInterceptor.beforeInvocation(AbstractSecurityInterceptor.java:254)

It is normal and shouldn't be anything to worry about.

You can check your customized filterSecurityInterceptor, and change the custom-filter position.