include/payment/alipay.php file, search (about 137 lines)
$order_sn = trim($_GET['out_trade_no']);
Modify to $order_sn = trim(addslashes($_GET['out_trade_no'])) ;;
$order_sn = trim($_GET['out_trade_no']);
Modify to $order_sn = trim(addslashes($_GET['out_trade_no'])) ;;