RedTeam Pentesting GmbH

ActiveWeb Contentserver CMS Clientside Filtering of Page Editor Content

RedTeam Pentesting discovered a design vulnerability in the page editor of the activeWeb contentserver CMS during a penetration test. Filtering of user content, e.g. to prevent the usage of Javascript code, is done on the client side. By manipulating the POST request, the filtering can be circumvented.

Details

Product: activeWeb contentserver
Affected Versions: <= 5.6.2929
Fixed Versions: 5.6.2964
Vulnerability Type: Design Flaw
Security-Risk: medium
Vendor-URL: http://www.active-web.de/aw/home/Produkte/~gf/contentserver/
Vendor-Status: informed, fixed version released
Advisory-URL: https://www.redteam-pentesting.de/advisories/rt-sa-2007-006
Advisory-Status: public
CVE: CVE-2007-3017
CVE-URL: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2007-3017

Introduction

contentserver is the comprehensive, scalable Content Management System for professional requirements. It combines editorial system, website management and development platform for web applications in one package.

(translation of the description on the vendor’s homepage)

More Details

The contentserver CMS provides a WYSIWYG (What You See Is What You Get) editor to edit articles in the browser. The editor is realised as a Java applet. As Javascript code is not allowed in articles, the editor filters any script tags.

When clicking the “save” icon, a POST request to

https://www.example.com/admin/applets/wysiwyg/rendereditor.asp

is sent. If one manipulates this request to contain Javascript, one is returned to the Java applet with the hint that script tags were removed. But, if the next POST request is manipulated, which goes to the script

https://www.example.com/admin/worklist/worklist_edit.asp

Javascript code can be embedded in the article, bypassing any filtering of the applet.

Fix

The vulnerability is fixed in release 5.6.2964.

Security Risk

Editors can embed arbitrary Javascript code in articles. An editor with malicious intent can use this to exploit any viewers accessing the website. The Javascript will also be executed in the management interface when viewing the article preview or editing the article. This means that an attacker may be able to steal the session cookie of other editors. The risk of this vulnerability is considered medium, as editors are normally considered trustworthy.

History

2007-05-23 Problem found during a penetration test
2007-05-30 Vendor notified by customer
2007-06-01 Vendor called back to discuss next steps and to announce
investigation
2007-06-29 Vendor confirmed the vulnerability
2007-06-29 CVE number assigned
2007-07-11 Vendor released fixed version
2007-07-13 Advisory released
2009-05-08 Updated Advisory URL

The vendor was very cooperative. There was always a competent contact person available who answered any questions.

RedTeam Pentesting offers individual penetration tests, short pentests, performed by a team of specialised IT-security experts. Hereby, security weaknesses in company networks or products are uncovered and can be fixed immediately.

As there are only few experts in this field, RedTeam Pentesting wants to share its knowledge and enhance the public knowledge with research in security-related areas. The results are made available as public security advisories.

More information about RedTeam Pentesting can be found at https://www.redteam-pentesting.de.