--- rdate-1.4/rdate.c.old	2017-12-11 12:08:17.722653301 +0100
+++ rdate-1.4/rdate.c	2017-12-11 12:08:41.988192170 +0100
@@ -69,7 +69,7 @@
     return; /* Error, which we can't report because this _is_ the error
 	       reporting mechanism */
   if(log_mode)
-    syslog(is_error?LOG_WARNING:LOG_INFO, buf);
+    syslog(is_error?LOG_WARNING:LOG_INFO, "%s", buf);
   if(is_error || print_mode)
     fprintf(is_error?stderr:stdout, "%s: %s\n", argv0, buf);
 }