diff --git a/gulliver/system/class.inputfilter.php b/gulliver/system/class.inputfilter.php
index 60cbfe689..ac99b71e6 100644
--- a/gulliver/system/class.inputfilter.php
+++ b/gulliver/system/class.inputfilter.php
@@ -352,6 +352,7 @@ class InputFilter
       * @param String $source
       * @param Resource $connection - An open MySQL connection
       * @return String $source
+      * @todo We need to review this method, because the sended string is unescaped
       */
     public function escapeString($string, &$connection)
     {
@@ -364,6 +365,19 @@ class InputFilter
         }
         return $string;
     }
+
+    /*
+     * Escapes a string using a Propel connection
+     *
+     * @param string $string The string to escapes
+     * @param object $connection The connection object
+     *
+     * @return string
+     */
+    public function escapeUsingConnection($string, $connection)
+    {
+        return mysql_real_escape_string($string, $connection->getResource());
+    }
     
     /** 
       * Internal method removes tags/special characters
diff --git a/workflow/engine/classes/Applications.php b/workflow/engine/classes/Applications.php
index 67857bb30..f58cccf6b 100644
--- a/workflow/engine/classes/Applications.php
+++ b/workflow/engine/classes/Applications.php
@@ -44,6 +44,23 @@ class Applications
 
         //Start the connection to database
         $con = Propel::getConnection(AppDelegationPeer::DATABASE_NAME);
+
+        //Sanitize input variables
+        $inputFilter = new InputFilter();
+        $userUid = $inputFilter->validateInput($userUid, 'int');
+        $start = $inputFilter->validateInput($start, 'int');
+        $limit = $inputFilter->validateInput($limit, 'int');
+        $search = $inputFilter->escapeUsingConnection($search, $con);
+        $process = $inputFilter->validateInput($process, 'int');
+        //$status doesn't require sanitization
+        $dir = in_array($dir, ['ASC', 'DESC']) ? $dir :'DESC';
+        $sort = $inputFilter->escapeUsingConnection($sort, $con);
+        $category = $inputFilter->escapeUsingConnection($category, $con);
+        $dateFrom = $inputFilter->escapeUsingConnection($dateFrom, $con);
+        $dateTo = $inputFilter->escapeUsingConnection($dateTo, $con);
+        $columnSearch = $inputFilter->escapeUsingConnection($columnSearch, $con);
+
+        //Start the transaction
         $con->begin();
         $stmt = $con->createStatement();