Check Point Advisories

Repeated Character Conversion Obfuscation

Vulnerability
Protection

Check Point Reference:	SBP-2011-12
Date Published:	6 Sep 2011
Severity:	High
Last Updated:	Thursday 30 May, 2013
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, Metasploit exploits could potentially bypass these security products by using JavaScript obfuscation techniques. An example of such a technique is the repeated character conversion obfuscation. 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-based exploits which use the repeated character obfuscation technique.

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 Repeated Character Conversion 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: Web Client Enforcement Violation.
Attack Information: Repeated character conversion obfuscation