XennoBB <= 2.2.1 "icon_topic" SQL Injection

[c.boulton () mybboard com]

--------------------- SUMMARY ---------------------

Name:
        XennoBB "icon_topic" SQL Injection (19/8/2006)

Vendor / Product:
        XennoBB Group
        http://www.xennobb.com/
        
        Description:
        The world's most revolutionary and easy to use bulletin board.

        Revolutionary because it redefines the boundaries of usability
        and power; from the first version it's a real alternative to
        the commercial forums out there.

        How can XennoBB be described in few words? 
        Lightning-speed, stable, SECURED(?) and modern.
        
Version(s) Affected:
        All current (<= 2.2.1 at the time of the release)
        
Severity:
        High
        
Impact:
        SQL Injection (Remote)

Status:
        Unpatched
        
Discovered by:
        Chris Boulton <http://www.surfionline.com>
        
Original advisory:
        http://www.surfionline.com/security_advisories/20060819_xennobb_icon_topic_sql.txt
        
------------------- DESCRIPTION -------------------

An exploit exists in the above mentioned versions of XennoBB which
can be exploited by malicious users to conduct SQL injection attacks.

Input passed to the "icon_topic" parameter in topic_post.php is not
properly sanitised before being used in an SQL query. This exploit
can lead to manipulation of SQL queries by injecting arbitary SQL code.

--------------------- EXPLOIT ---------------------

Submit a forged POST request to

topic_post.php?action=post&fid={forum ID here}

With the following as the POST data:

form_sent=1&form_user={username here}&req_subject=Subject&req_message=Message&submit=1&icon_topic=[SQL]

Successful exploitation leads would lead to the SQL query in the icon_topic
parameter being run.

--------------------- SOLUTION --------------------

Ensure input is properly sanitized before being used in a database
query.