copyright | disclaimer | privacy | contact  
Australia's Leading Computer Emergency Response Team
Search this site

On this site

 > About AusCERT
 > Membership
 > Contact Us
 > PKI Services
 > Publications
 > Sec. Bulletins
 > Conferences
 > News & Media
 > Services
 > Web Log
 > Site Map
 > Site Help
 > Member login


ESB-2009.1390 - [Win][UNIX/Linux] Shared Sign On (Drupal third-party module): Multiple vulnerabilities

Date: 12 October 2009

Click here for printable version
Click here for PGP verifiable version
Hash: SHA1

             AUSCERT External Security Bulletin Redistribution

        SA-CONTRIB-2009-069 - Shared Sign On - Cross Site Scripting
                              12 October 2009


        AusCERT Security Bulletin Summary

Product:           Shared Sign On (Drupal third-party module)
Publisher:         Drupal
Operating System:  UNIX variants (UNIX, Linux, OSX)
Impact/Access:     Cross-site Request Forgery -- Remote with User Interaction
                   Unauthorised Access        -- Remote with User Interaction
Resolution:        Patch/Upgrade
CVE Names:         CVE-2009-3656 CVE-2009-3657 

Original Bulletin:

- --------------------------BEGIN INCLUDED TEXT--------------------

SA-CONTRIB-2009-069 - Shared Sign On - Cross Site Scripting
Security advisories for contributed projects
Drupal Security Team - September 30, 2009 - 20:49

    * Advisory ID: DRUPAL-SA-CONTRIB-2009-069
    * Project: Shared Sign On (third-party module)
    * Version: 5.x, 6.x
    * Date: 2009 September 30
    * Security risk: Critical
    * Exploitable from: Remote
    * Vulnerability: Multiple vulnerabilities


The Shared Sign On module enables users to log into one Drupal site and be 
automatically logged into multiple related Drupal sites.

The module suffers multiple vulnerabilities, including Cross Site Request 
Forgeries (CSRF) and Session fixation problem (Session Fixation). This problem 
allows an attacker to hijack the account of a logged in user by tricking them 
into visiting a seemingly innocent page.

Versions affected

    * Versions of Shared Sign On for both Drupal 5.x and Drupal 6.x

Drupal core is not affected. If you do not use the contributed Shared Sign On 
module, there is nothing you need to do.


The Shared Sign On module is marked as un-supported. A separate project called 
Single Sign On has been created as a replacement. Download the Single Sign On 
module and carefully read the README.txt as there is a risk of breaking a site 
if instructions are not carried out correctly.

Reported by

    * Reported by Jose A. Reyero and Steven Wittens.

Fixed by

    * Fixed by Steven Wittens of Strutta Inc. and Jakub Suchy of Drupal Security 
team and Heine Deelstra of Drupal Security Team.


The security contact for Drupal can be reached at security at or via 
the form at

- --------------------------END INCLUDED TEXT--------------------

You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to
and we will forward your request to the appropriate person.

NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members.  As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.

NOTE: This is only the original release of the security bulletin.  It may
not be updated when updates to the original are made.  If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.

Contact information for the authors of the original document is included
in the Security Bulletin above.  If you have any questions or need further
information, please contact them directly.

Previous advisories and external security bulletins can be retrieved from:

If you believe that your computer system has been compromised or attacked in 
any way, we encourage you to let us know by completing the secure National IT 
Incident Reporting Form at:

Australian Computer Emergency Response Team
The University of Queensland
Qld 4072

Internet Email:
Facsimile:      (07) 3365 7031
Telephone:      (07) 3365 4417 (International: +61 7 3365 4417)
                AusCERT personnel answer during Queensland business hours
                which are GMT+10:00 (AEST).
                On call after hours for member emergencies only.