Uploading multiple files in Zend Framework 2 (solution for file is uploaded illegally in zf2)

IndexController.php

namespace Application\Controller;

use Zend\Mvc\Controller\AbstractActionController,
    Lists\Entity\Lists;

class IndexController extends AbstractActionController
{

    public function indexAction()
    {

        $listEntity = new Lists();

        $builder = new AnnotationBuilder();
        $form = $builder->createForm($listEntity);
        $form->setAttribute('enctype', 'multipart/form-data');

        $request = $this->getRequest();
        if ($request->isPost()) {

            $form->setValidationGroup('house_decision', 'house_wishlist', 'permit', 'inspection');
            $form->setData($request->getPost());

            if ($form->isValid()) {

                $files = $this->upload();
                if ($files['status'] == 'success') {

                    // save everything

                } else {

                    foreach ($files['messages'] as $key => $file) {
                        if ($file['status'] == 'error') {
                            $form->get($key)->setMessages($file['errors']);
                        }
                    }

                }   // $files['status'] == 'success'

            }   // isValid()

        }   // isPost()


        return new ViewModel(array(
            'form' => $form,
        ));
    }
    
    public function upload($allowed = array('pdf'))
    {


        $messages = array('status' => 'success');
        $files = $this->params()->fromFiles();
        foreach ($files as $key => $file) {

            if (!empty($file['name'])) {

                $adapter = new \Zend\File\Transfer\Adapter\Http();
                $size = new \Zend\Validator\File\Size(array('min' => 1, 'max' => 31457280)); // minimum bytes filesize, max too..
                $extension = new \Zend\Validator\File\Extension(array('extension' => $allowed));

                // rename file
                $rename = new \Zend\Filter\File\Rename(array(
                    'target' => str_replace(array(' ', '$'), '-', $file['name']),
                    'randomize' => true,
                    'overwrite' => true,
                ));

                $adapter->setValidators(array($size, $extension), $file['name']);
                $adapter->setFilters(array($rename), $file['name']);

                /**
                 * Valid Upload
                 */
                if ($adapter->isValid($key)) {  // $key is field name in the form

                    $adapter->setDestination('public/' . FILES_PATH);
                    if ($adapter->receive($key)) {  // $key is field name in the form

                        $uploadedFile = $adapter->getFileInfo();

                        $messages['status'] = 'success';
                        $messages['messages'][$key] = array(
                            'filename' => $uploadedFile[$key]['name'],
                            'status' => 'success',
                            'message' => 'File uploaded successfully!',
                        );
                    }

                } else {

                    $messages['status'] = 'error';
                    $messages['messages'][$key] = array(
                        'status' => 'error',
                        'errors' => $adapter->getMessages(),
                    );

                    break;
                }
            }   // !empty($file)


        }

        return $messages;

    }
    
}