OpenAM Open Redirect

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#  
# COMPASS SECURITY ADVISORY http://www.csnc.ch/en/downloads/advisories.html  
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#  
# CSNC ID: CSNC-2016-002  
# Product: OpenAM [1]  
# Vendor: ForgeRock  
# Subject: Open Redirect  
# Risk: Critical  
# Effect: Remotely exploitable  
# Author: Stephan Sekula ([email protected])  
# Date: February 23rd 2016  
#  
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Introduction:  
-------------  
OpenAM provides core identity services to simplify the implementation of  
transparent single sign-on (SSO) as a security component in a network  
infrastructure. OpenAM provides the foundation for integrating diverse  
web applications that might typically operate against a disparate set of  
identity repositories and are hosted on a variety of platforms such as  
web and application servers. [1]  
  
Compass Security discovered a web application security flaw in the OpenAM  
application which allows an attacker to launch phishing attacks against users  
by redirecting them to a malicious website. An attacker is able to create a  
link that, when visited, will redirect the user to a website of the attacker's  
choosing once the victim attempts to login. This allows, for instance,  
phishing of user credentials. Since it is the victim who needs to visit the  
malicious link, this attack is possible for unauthenticated attackers who do  
not have access to the affected websites.  
  
  
Affected Versions:  
------------------  
The following OpenAM versions are vulnerable:  
- 9.5.5  
- 10.0.2  
- 10.1.0-Xpress  
- 11.0.0-11.0.3  
- 12.0.0-12.0.2  
  
OpenAM version 13.0.0 is not vulnerable.  
  
  
Patches:  
--------  
OpenAM released patches for each affected version as part of OpenAM  
Security Advisory #201601 [2].  
  
  
Technical Description:  
----------------------  
OpenAM provides a whitelist mechanism that allows specifying allowed  
redirection URLs. If user input is not part of this whitelist, the user should  
be redirected to an error page. However, this mechanism only works for  
parameter values of the form "http://www.csnc.de" and "www.csnc.de". Parameter  
values such as "//www.csnc.de" will not be caught, thus effectively bypassing  
the whitelist mechanism.  
  
Example:  
/openam_sp/UI/Login?goto=//www.csnc.de&gotoOnFail=//www.csnc.de  
  
Exploiting the vulnerability will lead to redirections to arbitrary websites  
which allows phishing of user credentials.  
  
  
Milestones:  
-----------  
2015-12-16: Vulnerability discovered  
2016-01-04: Vendor notified  
2016-02-05: Vendor provided patched version  
2016-02-23: Public disclosure  
  
  
References:  
-----------  
[1] http://openam.forgerock.org/  
[2] https://forgerock.org/2016/02/openam-security-advisory-201601/  
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