===================================================================== CERT-Renater Note d'Information No. 2010/VULN280 _____________________________________________________________________ DATE : 04/08/2010 HARDWARE PLATFORM(S) : / OPERATING SYSTEM(S) : Systems running Citrix XenApp Online Plug-in for XenApp, Citrix XenApp Online Plug-in for XenDesktop, Citrix ICA Client, Citrix Receiver. ====================================================================== http://support.citrix.com/article/CTX125975 http://support.citrix.com/article/CTX125976 ______________________________________________________________________ Vulnerability in Citrix Online Plug-Ins and ICA Clients could result in arbitrary code execution Document ID: CTX125975 / Created On: Aug 2, 2010 / Updated On: Aug 3, 2010 Severity: High Description of Problem A vulnerability has been identified in the Citrix Online Plug-ins and ICA clients that could result in arbitrary code being executed in the context of the logged in user. If a user can be lured into invoking an ICA connection to a server controlled by the attacker, it may be possible for the attacker to execute arbitrary code on the client device in the context of the logged in user. ICA connections can be invoked by launching an .ICA file or by using an ICA client browser plug-in. For example, this could occur if a user visits an untrusted website or opens an untrusted e-mail attachment. What Customers Should Do Citrix has released updated versions of its Online Plug-ins and ICA clients to address this issue, and strongly recommends that customers install the latest versions of the following clients: Citrix Online Plug-in for Windows for XenApp & XenDesktop: This issue has been resolved in version 11.2 and later. However, due to the vulnerability described in CTX125976 - Vulnerability in Citrix XenApp Online Plug-in for Windows Could Result in Arbitrary Code Execution, Citrix recommends that customers upgrade to the latest version of this client, currently 12.0.3 which is available at the following location: http://citrix.com/English/ss/downloads/details.asp?downloadId=2301299&productId=186 Customers should note that there are currently known compatibility issues when using this client version in combination with Access Gateway configured to use the Access Interface. Customers using such a deployment should contact their Support representative for additional guidance. Citrix Online Plug-in for Mac for XenApp & XenDesktop: This issue has been resolved in version 11.0 and later. The latest version of this client is available from the following location: http://www.citrix.com/English/ss/downloads/details.asp?downloadId=1862769&productId=186&c1=sot2755 Citrix ICA Client for Linux (x86 and ARM): This issue has been resolved in version 11.100 and later. The latest version of this client is available from the following location: http://www.citrix.com/English/ss/downloads/details.asp?downloadId=3323&productId=186&c1=sot2755 Citrix ICA Client for Solaris (x86 and Sparc): This issue has been resolved in version 8.63 and later. The latest version of this client is available from the following location: http://www.citrix.com/English/ss/downloads/details.asp?downloadId=1859901&productId=186&c1=sot2755 Citrix Receiver for Windows Mobile: This issue has been resolved in version 11.5 and later. The latest version of this client is available from the following location: http://www.citrix.com/English/ss/downloads/results.asp?productID=186&c1=sot2755&c2=ost1859501 The ICA client for Java, the Citrix Receiver for iPhone/iPad, and the Citrix Receiver for Android are not affected by this vulnerability. Customers using client versions not mentioned in this document should contact their support representative for further guidance. Acknowledgements Citrix thanks Michael Jordon of Context Information Security Ltd. (http://www.contextis.co.uk/) for working with us to protect Citrix customers 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: * DOS Client * EPOC/Symbian Client * Java Client * Macintosh Client * UNIX Client * Windows (16 Bit) Client * XenApp Plug-in for Windows (32/64 Bit) ______________________________________________________________________________ Vulnerability in Citrix XenApp Online Plug-in for Windows Could Result in Arbitrary Code Execution Document ID: CTX125976 / Created On: Aug 2, 2010 / Updated On: Aug 3, 2010 Severity: High Description of Problem A vulnerability has been identified in the ICA Client ActiveX Object (ICO) component of the Citrix Online Plug-in for Windows that, when triggered, could allow an attacker to execute arbitrary code in the context of the currently logged in user. Where clients are configured to allow ActiveX objects to be launched by untrusted websites, there is a risk that the clients could be affected by this vulnerability. In such a deployment, the vulnerability could potentially be triggered by a malicious website that instantiates the ActiveX object. This vulnerability is present in all versions of the Online Plug-in for Windows up to version 12.0.3. Other platform versions of the Online Plug-in and ICA Clients are not affected by this vulnerability. Mitigating Factors By default, current versions of Internet Explorer will ask the user for consent before running non-preapproved ActiveX controls. What Customers Should Do This vulnerability has been addressed in the Citrix Online Plug-in for Windows version 12.0.3 and above. Customers should note that there are currently known compatibility issues when using this client version in combination with Access Gateway configured to use the Access Interface. Customers using such a deployment should contact their Support representative for additional guidance. Citrix strongly recommends that customers upgrade their Online Plug-ins to a version containing the fix for this issue. The new client package can be obtained from the following location: http://citrix.com/English/ss/downloads/details.asp?downloadId=2301299&productId=186 Acknowledgements Citrix would like to thank Sean of iDefense for working with us to protect Citrix customers. 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: * Windows (16 Bit) Client * XenApp Plug-in for Windows (32/64 Bit) ====================================================================== ========================================================= Les serveurs de référence du CERT-Renater http://www.urec.fr/securite http://www.cru.fr/securite http://www.renater.fr ========================================================= + CERT-RENATER | tel : 01-53-94-20-44 + + 151 bd de l'Hopital | fax : 01-53-94-20-41 + + 75013 Paris | email: certsvp@renater.fr + =========================================================