Finally found out the error:
In SpringSecurity 4.x, CasAuthenticationFilter's defaultFilterProcessesUrl path is changed. So Change '/j_spring_cas_security_check' to '/login/cas' in Configuration.
So in my application.properties file, i had to change
app.service.security=http://localhost:7777/j_spring_cas_security_check
to
app.service.security=http://localhost:7777/login/cas
So the ServiceProperties Bean would become
@Bean
public ServiceProperties serviceProperties() {
ServiceProperties serviceProperties = new ServiceProperties();
serviceProperties.setService("http://localhost:7777/login/cas");
serviceProperties.setSendRenew(false);
return serviceProperties;
}
Hope it'll help someone else!