Secunia

Andrew Christensen has reported a security issue in various Citrix products, which can be exploited by malicious people to bypass certain security restrictions.

The problem is that the Session Reliability Service allows the client to specify a target host and port to connect to. This can be exploited to e.g. bypass network security policies and connect to arbitrary ports on a target machine.

Successful exploitation requires that the Session Reliability feature is enabled.

The security issue affects the following products:
* Citrix MetaFrame Presentation Server 3.0
* Citrix Presentation Server 4.0
* Citrix Access Essentials 1.0
* Citrix Access Essentials 1.5

Solution
Apply hotfix.
Further details available in Customer Area

Provided and/or discovered by
Andrew Christensen, FortConsult

Changelog
Further details available in Customer Area

Original Advisory
Citrix:
http://support.citrix.com/article/CTX112964

FortConsult:
http://www.fortconsult.net/images/pdf/Citrix_Session-Reliability_OpenProxy.pdf

Deep Links
Links available in Customer Area