Original Photo Gallery Remote Command Execution

`Original Photo Gallery Remote Command Execution  
  
Name Original Photo Gallery Remote Command Execution  
Systems Affected Original 0.11.2 version and below  
Severity High  
Vendor http://jimmac.musichall.cz/original.php  
Advisory  
http://www.ush.it/team/ascii/hack-original/advisory_updated.txt  
http://www.ush.it/team/ascii/hack-original/advisory.txt  
Author Francesco `ascii` Ongaro, Antonio `s4tan` Parata  
Date 20070919  
  
I. BACKGROUND  
  
"Original is a set of scripts to get your digital photos on the web. It  
aims to be as simple to maintain as possible."  
  
The systems consist of two parts: "a client side script to scale your  
images to different sizes, create archives of an album, attach optional  
metadata" and a "php script to render html pages of the picture  
gallery".  
  
II. DESCRIPTION  
  
It's possible to execute arbitrary code on remote systems which have  
installed a vulnerable software version.  
  
III. ANALYSIS  
  
The file "inc/exif.inc.php" contains the following vulnerable statement:  
  
exec("$exif_prog \"$gallery_dir/$galerie/lq/img-$snimek.jpg\"",  
$exif_data, $exif_status);".  
  
If PHP is configured with the "globals on" option, an attacker can  
execute arbitrary code doing a direct request to the file and sending  
shell commands in the parameter/value $exif_prog.  
  
IV. DETECTION  
  
http://www.x.com/original/inc/exif.inc.php?exif_prog=/path/to/touch%20/tmp/p0wn3d.txt;  
  
The request should create a file in the /tmp directory (on Unix systems)  
named p0wn3d.txt. If this happens than you have a vulnerable version of  
the software (and a really risky PHP setup).  
  
A rapid measurement show that ~10% systems are vulnerable of about  
17'000 listed on Google (using the dork: "Generated by Original ver").  
  
V. WORKAROUND  
  
Upgrade to the new version 0.11.3 witch fix this vulnerability.  
  
http://jimmac.musichall.cz/zip/original/original-0.11.3.tar.bz2  
  
Or if unable to upgrade:  
  
1) Disable access to the directory using Limit (vhosts/.htaccess).  
  
2) Disable execution using disable_functions in php.ini.  
  
The result is:  
  
Warning: exec() has been disabled for security reasons in  
/home/XXX/inc/exif.inc.php on line 157  
  
3) Deny direct access to the file in the PHP code by checking for a  
define or requested url.  
  
VI. VENDOR RESPONSE  
  
The vendor has promptly replied and addressed the problem issuing a  
new release.  
  
Original version 0.11.3 is available here:  
  
http://jimmac.musichall.cz/zip/original/original-0.11.3.tar.bz2  
  
VII. CVE INFORMATION  
  
No CVE at this time.  
  
VIII. DISCLOSURE TIMELINE  
  
20070719 Bug discovered  
20070725 Vendor contacted  
20070927 Vendor reply and fix  
20071002 Advisory released  
  
IX. CREDIT  
  
Francesco `ascii` Ongaro and Antonio `s4tan` Parata are credited with  
the discovery of this vulnerability.  
  
X. LEGAL NOTICES  
  
Copyright (c) 2007 Francesco `ascii` Ongaro  
  
Note: this exploit is DUAL LICENSED,  
1. if you'll use it for personal and non-profit purposes you can  
apply GPL v2 and above.  
  
2. In the case you plain to:  
a. use our code in any commercial context  
b. implement this code in your non-GPL application  
c. use this code during a Penetration Test  
d. make any profit from it  
  
you need to contact me in order to obtain a _commercial license_.  
  
For more informations about Dual Licensing:  
http://producingoss.com/html-chunk/dual-licensing.html  
  
Permission is granted for the redistribution of this alert  
electronically. It may not be edited in any way without mine express  
written consent. If you wish to reprint the whole or any  
part of this alert in any other medium other than electronically, please  
email me for permission.  
  
Disclaimer: The information in the advisory is believed to be accurate  
at the time of publishing based on currently available information. Use  
of the information constitutes acceptance for use in an AS IS condition.  
There are no warranties with regard to this information. Neither the  
author nor the publisher accepts any liability for any direct, indirect,  
or consequential loss or damage arising from use of, or reliance on,  
this information.  
  
`