Check Point Advisories

Citrix Presentation Server Client wfica.ocx Buffer Overflow (CVE-2006-6334)

Vulnerability
Protection

Check Point Reference:	CPAI-2007-019
Date Published:	14 Jan 2007
Severity:	Critical
Last Updated:	Sunday 14 January, 2007
Source:
Industry Reference:	CVE-2006-6334
Protection Provided by:	Security Gateway R81, R80, R77, R75, R71, R70, R65
Who is Vulnerable?
Vulnerability Description	Citrix Presentation Server, a remote access application publishing product, is prone to a buffer overflow vulnerability. By convincing a user to visit a malicious Web page or open a malicious HTML, a remote attacker could cause the victim's system to execute arbitrary commands and take complete control over the affected system.The vulnerability is due to a buffer overflow error in the ICA Client ActiveX Control (WFICA.OCX). The flaw occurs when processing specially crafted arguments passed to the 'SendChannelData' function. To trigger the vulnerability, an attacker can create a malicious Web page that initiates the ActiveX control with a specially crafted argument. Successful exploitation could result in remote code execution on the victim's system once the malicious page is loaded.

Protection Overview

This protection will detect and block the vulnerable ActiveX Control application.

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 / R71 / R70 / R65

In the IPS tab, click Protections and find the Citrix Presentation Server Client wfica.ocx Buffer Overflow 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: Web Client Enforcement Violation.
Attack Information: Citrix presentation server client wfica.ocx buffer overflow