diff -uNr BUILD/samba-4.6.2/source3/winbindd/winbindd_pam.c samba-4.6.2-patchfc/source3/winbindd/winbindd_pam.c
--- BUILD/samba-4.6.2/source3/winbindd/winbindd_pam.c	2017-01-11 02:55:15.000000000 -0500
+++ samba-4.6.2-patchfc/source3/winbindd/winbindd_pam.c	2018-03-20 12:15:30.001653041 -0400
@@ -1713,7 +1713,7 @@
 	DEBUG(10,("winbindd_dual_pam_auth: domain: %s last was %s\n", domain->name, domain->online ? "online":"offline"));
 
 	/* Check for Kerberos authentication */
-	if (domain->online && (state->request->flags & WBFLAG_PAM_KRB5)) {
+	if ((domain->online || !(domain->domain_flags & NETR_TRUST_FLAG_INBOUND)) && (state->request->flags & WBFLAG_PAM_KRB5)) {
 
 		result = winbindd_dual_pam_auth_kerberos(domain, state, &info3);
 		/* save for later */
@@ -1762,7 +1762,7 @@
 
 sam_logon:
 	/* Check for Samlogon authentication */
-	if (domain->online) {
+	if (domain->online || !(domain->domain_flags & NETR_TRUST_FLAG_INBOUND)) {
 		result = winbindd_dual_pam_auth_samlogon(
 			state->mem_ctx, domain,
 			state->request->data.auth.user,