Check Point Advisories

Internet Explorer findText Unicode Parsing Denial of Service (CVE-2009-2655)

Vulnerability
Protection

Check Point Reference:	CPAI-2011-005
Date Published:	19 Jan 2011
Severity:	Medium
Last Updated:	Wednesday 19 January, 2011
Source:
Industry Reference:	CVE-2009-2655
Protection Provided by:	Security Gateway R81, R80, R77, R75, R71, R70, R65
Who is Vulnerable?
Vulnerability Description	Microsoft Internet Explorer is the most widely used Internet browser. A denial of service vulnerability has been reported in the way Microsoft Internet Explorer parses HTML pages. The vulnerability is due to an error in the mshtml.dll library. A remote attacker might exploit this issue by persuading a user to visit a specially crafted Web page that calls the JavaScript findText method with a crafted Unicode string in the first argument and only one additional argument. Successful exploitation of this vulnerability would create a denial of service condition, causing the browser to crash.

Protection Overview

This protection will detect and block attempts to exploit this vulnerability via malicious HTML pages.

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 Internet Explorer findText Unicode Parsing Denial of Service 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: Internet Explorer findText Unicode parsing denial of service