Update ajax_get_json.php

Author: Till Brehm

interface/web/dns/ajax_get_json.php

@@ -35,7 +35,7 @@
 $app->auth->check_module_permissions('dns');
 
 $type = $_GET["type"];
-$ca_id = $_GET['ca_id'];
+$ca_id = $app->functions->intval($_GET['ca_id']);
 
 if($type == 'get_ipv4'){
 	$result = array();