diff -urN a/PAM.cpp b/PAM.cpp
--- a/PAM.cpp	2013-10-02 02:38:05.000000000 +0400
+++ b/PAM.cpp	2021-10-06 01:51:00.071704941 +0300
@@ -127,6 +126,7 @@
 			case PAM_MAXTRIES:
 			case PAM_CRED_INSUFFICIENT:
 			case PAM_AUTH_ERR:
+			case PAM_PERM_DENIED:
 				throw Auth_Exception(pam_handle, "pam_authentication()", last_result);
 
 			case PAM_SUCCESS: