CAS Authentication - CSRF Token Not Found

Question

CAS Authentication - CSRF Token Not Found

I am using Apereo CAS (formerly Jasig CAS) ( github here ). Then I create a very simple application in Vaadin that connects to CAS during authentication. Everything worked without problems until I turned on CSRF from Spring Security .

If CSRF is enabled, redirecting to the CAS login page works fine. But after successful authentication (login, passoword), CAS wants to redirect back to my application. Then I see the following:

{
  "timestamp": 1498657046424,
  "status": 403,
  "error": "Forbidden",
  "message": "Invalid CSRF Token 'null' was found on the request parameter '_csrf' or header 'X-XSRF-TOKEN'.",
  "path": "/contextPath/"
}

I am using Spring Boot @EnableWebSecurity, so please take a look at the configuration from there:

@Override
protected void configure(HttpSecurity http) throws Exception {
    http
        .addFilter(casAuthenticationFilter())
        .addFilterBefore(singleSignOutFilter(), CasAuthenticationFilter.class)
        .exceptionHandling()
            .authenticationEntryPoint(casAuthenticationEntryPoint())
            .and()
        .authorizeRequests()
            .antMatchers("/login")
            .permitAll()
        .anyRequest()
            .authenticated();


    http.csrf().disable(); //works when disable
}