Check Point Advisories

Citrix Program Neighborhood Agent Arbitrary Shortcut Creation (CVE-2004-1077)

Vulnerability
Protection

Check Point Reference:	CPAI-2005-231
Date Published:	28 Dec 2009
Severity:	High
Last Updated:	Monday 28 December, 2009
Source:
Industry Reference:	CVE-2004-1077
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?
Vulnerability Description	Citrix Presentation Server, formally known as Citrix MetaFrame, is designed for central application deployment. This package allows applications to be deployed and managed by a farm of dedicated servers and allow client machines to access these applications remotely. There exists an arbitrary shortcut creation vulnerability in the Citrix Program Neighborhood Agent. The problem can be triggered by sending a crafted XML response to an affected client. Successful exploitation can allow creation of arbitrary shortcuts which can result in code execution with the privileges of the current user. In an attack scenario, one of more Published Applications configuration files are added to the current user's Startup folder with ".pnagent" extensions. After a subsequent reboot of the affected machine, entries in the Startup folder are launched automatically. The vulnerable Neighborhood Agent application will automatically launch the remote applications on the Metaframe server. A malicious application may be served which writes arbitrary executable files to the target user's local file system system. Executable files may be placed in the Startup folder in order to ensure automatic execution upon next system restart. Note that the non-vulnerable version of the software will still add pnagent files to the Startup folder upon receiving crafted XML contents, however, it will refuse to launch these files from the Startup folder.

Protection Overview

This protection will detect and block attempts to exploit this vulnerability.

In order for the protection to be activated, update your Security Gateway product to the latest IPS update. For information on how to update IPS, go to SBP-2006-05, click on Protection tab and select the version of your choice.

Security Gateway R80 / R77 / R75

In the IPS tab, click Protections and find the Citrix Program Neighborhood Agent Arbitrary Shortcut Creation protection using the Search tool and Edit the protection's settings.
Install policy on all Security Gateways.

This protection's log will contain the following information:

Attack Name: Citrix ICA Protection Violation.
Attack Information: Citrix Program Neighborhood agent arbitrary shortcut creation