BLUE MOON SECURITY ADVISORY 2009-08

Title:Multiple Vulnerabilities in PyForum
Severity:Critical
Reporter:Hoang Quoc Thinh and Blue Moon Consulting
Products:PyForum v1.0.3
Fixed in:--

Description

PyForum is a 100% python-based message board system based in the excellent web2py framework.

We have discovered cross site scripting and cross site request forgery vulnerabilities in PyForum. The first allows arbitrary script to run when a post is viewed. The second allows attackers to submit forms (such as changing password) automatically without user's knowledge.

XSS vulnerability lies in the BBcode parsing in module models.parser. The img and url tags do not sanitize inputs and hence are susceptible to script injection.

CSRF vulnerability lies in the design of this web application. Forms do not have secure cookies and may be automatically submitted on behalf of the user.

These bugs are rated at critical because they can be easily exploited and cause lost of integrity.

These bugs may exist in older versions and in zForum, from which pyForum derives, too.

Workaround

There is no workaround.

Fix

There is no fix at the moment.

Disclosure

Blue Moon Consulting adapts RFPolicy v2.0 in notifying vendors.

Initial vendor contact:
 

December 05, 2009: Notice sent to Julio Flores Schwarzbeck (techfuel.net)

December 09, 2009: Reminder sent to Julio Flores Schwarzbeck

Vendor response:
 

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Further communication:
 

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Public disclosure:
 

December 15, 2009

Exploit code:

No exploit code required.

Disclaimer

The information provided in this advisory is provided "as is" without warranty of any kind. Blue Moon Consulting Co., Ltd disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. Your use of the information on the advisory or materials linked from the advisory is at your own risk. Blue Moon Consulting Co., Ltd reserves the right to change or update this notice at any time.