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16 July 2009

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             AUSCERT External Security Bulletin Redistribution

          Vulnerability in XenApp 4.5 Hotfix Rollup Pack 3 could
                          result in policy bypass
                               16 July 2009


        AusCERT Security Bulletin Summary

Product:           XenApp 4.5
Publisher:         Citrix
Operating System:  Windows
Impact/Access:     Unauthorised Access -- Existing Account
Resolution:        Patch
CVE Names:         CVE-2009-2453  

Original Bulletin: 

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

Vulnerability in XenApp 4.5 Hotfix Rollup Pack 3 could result in policy 

Document ID: CTX118792 / Created On: Apr 22, 2009 / Updated On: Apr 22, 2009
Average Rating: 5 (1 ratings)

Severity: Medium

Description of Problem

A vulnerability has been identified in XenApp (formerly Presentation Server)
4.5 Hotfix Rollup Pack 3 that could result in an access policy defined using
the Access Gateway filters not being applied.

This vulnerability only affects XenApp deployments where Hotfix Rollup 
Pack 3 is installed and Access Gateway Advanced Edition filters are being 

Mitigating Factors

The standard XenApp published application authorization policies, based on 
users or groups, are not affected by this vulnerability.

What Customers Should Do

This vulnerability has been addressed in Hotfix Rollup Pack 4 for XenApp 
4.5. Citrix recommends that affected customers apply this Hotfix Rollup 
Pack, which can be obtained from the following locations:

Citrix XenApp 4.5 for Windows Server 2003:

EN - http://support.citrix.com/article/CTX119069

ES - http://support.citrix.com/article/CTX119074

FR - http://support.citrix.com/article/CTX119071

DE - http://support.citrix.com/article/CTX119072

JA - http://support.citrix.com/article/CTX119073

RU - http://support.citrix.com/article/CTX119471

Citrix XenApp 4.5 for Windows Server 2003 x64 Editions:

EN - http://support.citrix.com/article/CTX119075

ES - http://support.citrix.com/article/CTX119079

FR - http://support.citrix.com/article/CTX119076

DE - http://support.citrix.com/article/CTX119077

JA - http://support.citrix.com/article/CTX119078

What Citrix Is Doing

Citrix is notifying customers and channel partners about this potential 
security issue. This article is also available from the Citrix Knowledge 
Center at http://support.citrix.com/.

Obtaining Support on This Issue

If you require technical assistance with this issue, please contact Citrix 
Technical Support. Contact details for Citrix Technical Support are 
available at http://www.citrix.com/site/ss/supportContacts.asp.

Reporting Security Vulnerabilities to Citrix

Citrix welcomes input regarding the security of its products and considers 
any and all potential vulnerabilities seriously. If you would like to report 
a security issue to Citrix, please compose an e-mail to secure@citrix.com 
stating the exact version of the product in which the vulnerability was 
found and the steps needed to reproduce the vulnerability

This document applies to:

    * Feature Pack 1 for Presentation Server 4.5
    * Presentation Server 4.5 SE Edition
    * Presentation Server 4.5 for Windows Server 2003
    * Presentation Server 4.5 for Windows Server 2003 x64 Edition

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

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