diff -up cronie-1.4.11/src/security.c.no-pam cronie-1.4.11/src/security.c
--- cronie-1.4.11/src/security.c.no-pam	2017-03-07 15:17:14.610948157 +0100
+++ cronie-1.4.11/src/security.c	2017-09-15 09:36:26.709112459 +0200
@@ -86,6 +86,7 @@ static int cron_open_pam_session(struct
 		if (pam_session_opened != 0) \
 			pam_close_session(pamh, PAM_SILENT); \
 		pam_end(pamh, retcode); \
+		pamh = NULL; \
 	} \
 return(retcode); }
 #endif
@@ -221,7 +222,10 @@ void cron_close_pam(void) {
 		pam_setcred(pamh, PAM_DELETE_CRED | PAM_SILENT);
 		pam_close_session(pamh, PAM_SILENT);
 	}
-	pam_end(pamh, PAM_SUCCESS);
+	if (pamh != NULL) {
+		pam_end(pamh, PAM_SUCCESS);
+		pamh = NULL;
+	}
 #endif
 }