diff --git a/includes/services/check_smtp.inc.php b/includes/services/check_smtp.inc.php
index 39b0a61431..c3af27bd7f 100644
--- a/includes/services/check_smtp.inc.php
+++ b/includes/services/check_smtp.inc.php
@@ -1,2 +1,2 @@
 <?php
-$check_cmd = shell_exec($config['nagios_plugins'] . "/check_smtp -H ".$service['hostname']);
+$check_cmd = $config['nagios_plugins'] . "/check_smtp -H ".$service['hostname'];