diff --git a/web/skins/classic/views/filter.php b/web/skins/classic/views/filter.php
index 53f7a03b7..8071496c5 100644
--- a/web/skins/classic/views/filter.php
+++ b/web/skins/classic/views/filter.php
@@ -38,7 +38,8 @@ $fid = 0;
 if ( isset($_REQUEST['Id']) and $_REQUEST['Id'] ) {
   $fid = validInt($_REQUEST['Id']);
 } else if ( isset($_REQUEST['filter']) and isset($_REQUEST['filter']['Id']) ) {
-  $fid = validInt($_REQUEST['filter']['Id']);
+  # $_REQUEST['filter']['Id'] get used later in populating filter object, so need to sanitise it
+  $fid = $_REQUEST['filter']['Id'] = validInt($_REQUEST['filter']['Id']);
 }
 $filter = null;
 foreach ( ZM\Filter::find(null,array('order'=>'lower(Name)')) as $Filter ) {