Archive: Vulnerability in Citrix Presentation Server's Session Reliability service could result in network security policy bypass
This article is no longer maintained, its content refers to a discontinued product and may be out of date. Refer to the Discontinued Product Lifecycle or Active Citrix Product pages for more information on support schedules
Applicable Products
- Access Essentials 1.0
- Access Essentials 1.5
- Presentation Server 4.0 and Components
- Presentation Server 4.0 x64 Edition
Description of Problem
The Session Reliability service is used by some Citrix products to improve user experience when connecting over unreliable networks. By sending a specifically crafted request to this service, an attacker could establish a TCP connection to any port on the local machine. This could be used by the attacker to bypass network security policies and remotely access local ports on the target machine.
This vulnerability is present in the following versions of Citrix products:
• Citrix MetaFrame Presentation Server 3.0
• Citrix Presentation Server 4.0
• Citrix Access Essentials 1.0
• Citrix Access Essentials 1.5
No other versions of Citrix Presentation Server, Citrix Access Essentials or Citrix Desktop Server are affected by this issue.
Customers running an affected product with the Session Reliability feature disabled are not affected by this issue.
What Customers Should Do
A hotfix has been released to address this issue. Citrix recommends that affected customers install this hotfix, which can be downloaded from the following locations:
MetaFrame Presentation Server 3.0 for Windows 2000 Server:
EN - http://support.citrix.com/article/CTX112818
FR - http://support.citrix.com/article/CTX112821
DE - http://support.citrix.com/article/CTX112819
JA - http://support.citrix.com/article/CTX112820
ES - http://support.citrix.com/article/CTX112822
MetaFrame Presentation Server 3.0 for Windows Server 2003:
EN - http://support.citrix.com/article/CTX112813
FR - http://support.citrix.com/article/CTX112816
DE - http://support.citrix.com/article/CTX112814
JA - http://support.citrix.com/article/CTX112815
ES - http://support.citrix.com/article/CTX112817
Citrix Presentation Server 4.0 for Windows 2000 Server:
EN - http://support.citrix.com/article/CTX112844
FR - http://support.citrix.com/article/CTX112847
DE - http://support.citrix.com/article/CTX112845
JA - http://support.citrix.com/article/CTX112848
ES - http://support.citrix.com/article/CTX112846
Citrix Presentation Server 4.0 for Windows Server 2003:
EN - http://support.citrix.com/article/CTX112839
FR - http://support.citrix.com/article/CTX112842
DE - http://support.citrix.com/article/CTX112840
JA - http://support.citrix.com/article/CTX112843
ES - http://support.citrix.com/article/CTX112841
Citrix Presentation Server 4.0 for Windows Server 2003 x64 Editions:
EN - http://support.citrix.com/article/CTX112886
FR - http://support.citrix.com/article/CTX112887
DE - http://support.citrix.com/article/CTX112888
JA - http://support.citrix.com/article/CTX112890
ES - http://support.citrix.com/article/CTX112889
Citrix Access Essentials 1.0:
EN - http://support.citrix.com/article/CTX112839
FR - http://support.citrix.com/article/CTX112842
DE - http://support.citrix.com/article/CTX112840
ES - http://support.citrix.com/article/CTX112841
Citrix Access Essentials 1.5:
EN - http://support.citrix.com/article/CTX112839
FR - http://support.citrix.com/article/CTX112842
DE - http://support.citrix.com/article/CTX112840
ES - http://support.citrix.com/article/CTX112841
Acknowledgements
Citrix thanks Andrew Christensen of FortConsult working with us to protect Citrix customers.
What Citrix Is Doing
Citrix is proactively notifying customers and channel partners about this potential security issue. This article is also available from the Citrix Knowledge Base at http://support.citrix.com/ .
Obtaining Support on this Issue
If you require technical assistance with this issue, please contact Citrix Technical Support. Information for contacting Citrix Technical Support is available at http://support.citrix.com/.
Reporting Security Vulnerabilities to Citrix
Citrix welcomes input regarding the security of its products and considers any and all potential vulnerabilities very seriously. If you would like to report a security issue to Citrix, please compose an e-mail to secure@citrix.com containing the exact version of the product in which the vulnerability was found and the steps needed to reproduce the vulnerability.