Example: I first crafted a file that contains:
Edit: MaXe reported that I have trash in the output because my payload doesn't follow JPEG standards.
(A black dot in a GIF File + phpinfo();
Here I am uploading the file with the vulnerability:
Cache folder has our file:
Executing the script:
# Exploit Title: WordPress TimThumb Plugin - Remote Code Execution
# Google Dork: inurl:timthumb ext:php -site:googlecode.com -site:google.com
# Date: 3rd August 2011
# Author: MaXe
# Software Link: http://timthumb.googlecode.com/svn-history/r141/trunk/timthumb.php
# Version: 1.32
# Screenshot: See attachment
# Tested on: Windows XP + Apache + PHP (XAMPP)
WordPress TimThumb (Theme) Plugin - Remote Code Execution
1.* - 1.32 (Only version 1.19 and 1.32 were tested.)
(Version 1.33 did not save the cache file as .php)
Info: (See references for original advisory)
TimThumb is an image resizing utility, widely used in many WordPress themes.
- Mark Maunder (Original Researcher)
- MaXe (Indepedendent Proof of Concept Writer)
-:: The Advisory ::-
TimThumb is prone to a Remote Code Execution vulnerability, due to the
script does not check remotely cached files properly. By crafting a
special image file with a valid MIME-type, and appending a PHP file at
the end of this, it is possible to fool TimThumb into believing that it
is a legitimate image, thus caching it locally in the cache directory.
Attack URL: (Note! Some websites uses Base64 Encoding of the src GET-request.)
Stored file on the Target: (This can change from host to host.)
md5($src); means the input value of the 'src' GET-request - Hashed in MD5 format.
Proof of Concept File:
(Transparent GIF +
-:: Solution ::-
Update to the latest version 1.34 or delete the timthumb file.
NOTE: This file is often renamed and you should therefore issue
a command like this in a terminal: (Thanks to rAWjAW for this info.)
find . | grep php | xargs grep -s timthumb
- Vulnerability Disclosed (Mark Maunder): 1st August 2011
- Vulnerability Researched (MaXe): 2nd August 2011
- Disclosed at The Exploit Database: 3rd August 2011