SEC-2753: NullPointerException in AccountStatusUserDetailsChecker

Gar Greenberg (Migrated from SEC-2753) said:

When user was successfully authenticated in LDAP but did not have permissions to access the software an NPE occurs:
java.lang.NullPointerException
org.springframework.security.authentication.AccountStatusUserDetailsChecker.check(AccountStatusUserDetailsChecker.java:16)
org.springframework.security.cas.authentication.CasAuthenticationProvider.authenticateNow(CasAuthenticationProvider.java:133)
org.springframework.security.cas.authentication.CasAuthenticationProvider.authenticate(CasAuthenticationProvider.java:117)
com.rhd.ams.security.cas.ams.CasBasicAuthenticationProvider.authenticate(CasBasicAuthenticationProvider.java:56)
org.springframework.security.authentication.ProviderManager.authenticate(ProviderManager.java:156)
com.rhd.ams.security.cas.ams.CustomBasicAuthenticationFilter.doFilter(CustomBasicAuthenticationFilter.java:172)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:87)
org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:323)
org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:173)
org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:346)
org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:259)

Start with AccountStatusUserDetailsChecker.java at line 16 and trace how CasAuthenticationProvider.authenticateNow reaches it after successful LDAP authentication. Reproduce the case where the user lacks permissions, then determine the expected authentication outcome and verify that the NPE no longer occurs through the reported authentication path.