Check Point Advisories

Javascript eval Case Sensitivity Obfuscation

Vulnerability
Protection

Check Point Reference:	SBP-2011-01
Date Published:	18 Oct 2010
Severity:	High
Last Updated:	Monday 18 October, 2010
Source:
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?
Vulnerability Description	Although various security products provide coverage against many web vulnerabilities, such as ActiveX exploits, these known exploits could potentially bypass security products by using JavaScript obfuscation techniques. An example of such a technique is the JavaScript "eval" obfuscation, which is exploited for running malicious JavaScript code by obfuscating the usage of the function. Such techniques obfuscate known exploits so they will bypass security rules - since the exploits are being thoroughly obfuscated, IDS and IPS systems will not recognize them and thus will allow them to pass without any notification.

Protection Overview

This protection will detect and block Metasploit attacks which use the JavaScript "eval" obfuscation.

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 Javascript eval Case Sensitivity Obfuscation 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: Security Products Enforcement Violation.
Attack Information: Javascript eval case sensitivity obfuscation