Check Point Advisories

Internet Explorer execCommand File Type Spoofing (CVE-2004-1331)

Vulnerability
Protection

Check Point Reference:	CPAI-2004-198
Date Published:	19 Nov 2009
Severity:	Medium
Last Updated:	Thursday 19 November, 2009
Source:
Industry Reference:	CVE-2004-1331
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?
Vulnerability Description	Internet Explorer is a popular web-browser released by the Microsoft Corporation. It supports various content available on the web including HTML documents, images, dynamic scripting, and so on. Internet Explorer also provides the Dynamic Hypertext Markup Language (DHTML) application programming interface (API). A vulnerability exists in Microsoft Internet Explorer when the script command execCommand is used to save a document. A specially crafted filename will be displayed as another file type. An attacker can exploit this vulnerability to save code to the target system with the extension of an executable program (e.g. .js file) by tricking a user into believing that he is saving a non-executable file (e.g., .html file). The vulnerable application will not exhibit any unusual behaviour during or after a successful attack. The download dialog box will present the file like a normal HTML file but will save it with the full name including the executable extension. Upon execution of the malicious downloaded file, the behaviour of the attack target is entirely dependent on the nature of the injected code. The code is executed in the security context of the currently logged in user.

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 Internet Explorer execCommand File Type Spoofing 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: Microsoft Internet Explorer execCommand file type spoofing