LS Simple Guestbook 1.0 - Remote Code Execution

EDB-ID:

3735


Platform:

PHP

Published:

2007-04-14

########################################################
#   Special Greetings To - Timq,Warpboy,The-Maggot     #
########################################################

File: index.php
Affects: LS simple guestbook (v1)
Date: 15th April 2007

Issue Description:
===========================================================================
LS simple guestbook fails to sanitize user input that it writes to the
posts.txt file when the user leaves a message, this file is then included
causing any php code within it to be run.
===========================================================================

Scope:
===========================================================================
An attacker can inject arbitrary php code and potentially execute commands
on the system.
===========================================================================

Recommendation:
===========================================================================
Add the following line of code in index.php:

$message = strip_tags($message);

just above:

if ($message != "") {$file = fopen("$dataf","a");
===========================================================================


Example:

name = Test
message = <?php phpinfo(); ?>


Discovered By: Gammarays

# milw0rm.com [2007-04-14]