Update Protection against Mozilla Network Security Services and Firefox Common Name Security Bypass

Vulnerability
Protection

Check Point Reference:	CPAI-2009-129
Date Published:
Severity:
Last Updated:
Source:	Mozilla Foundation Security Advisory 2009-42
Industry Reference(s):	CVE-2009-2408 CVE-2009-4565
Protection Provided by:	Security Gateway R70 VPN-1 NGX R65 VSX NGX R65 IPS-1 IPS-1 IPS-1 NGX R65
Who is Vulnerable? Mozilla Foundation Firefox 3.0.12 and prior Mozilla Foundation Network Security Services Prior to 3.12.3
Vulnerability Description A security bypass vulnerability has been reported in Mozilla Network Security Services (NSS) and Firefox. Network Security Services (NSS) is a set of libraries designed to support cross-platform development of security-enabled client and server applications. Firefox is a popular, open source web browser developed by Mozilla Foundation. A remote attacker could exploit this flaw to execute a man-in-the-middle attack on the vulnerable system.

Update/Patch Available
Apply patch:
Red Hat Bugzilla – Bug 510251

Vulnerability Details
The vulnerability is due to an error in Mozilla Firefox and NSS when handling NULL characters in a domain name in the subject's Common Name (CN) field of a certificate. A remote attacker can exploit this flaw by sending a malicious certificate to a vulnerable system. Successful exploitation could allow man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority.

Protection Overview
This protection will detect and block NULL prefix found in SSL certificates.

In order for the protection to be activated, update your Security Gateway/VPN-1 product to the latest IPS/SmartDefense update. For information on how to update IPS/SmartDefense, go to SBP-2006-05, Protection tab and select the version of your choice.

To configure the defense, select your product from the list below and follow the related protection steps.

Security Gateway R70

How Can I Protect My Network?
1. In the IPS tab, click Protections > By Protocol > Web Intelligence > HTTP Client Protections.
2. In the right pane, double-click the SSL NULL Termination Certificate Validation Security Bypass protection.
3. In the Protection Details window, click on Edit. Choose the protection's Action (Override IPS Policy with: Prevent/Detect), and apply Additional Settings.
4. Install policy on all modules.

How Do I Know if My Network is Under Attack?
SmartView Tracker will log the following entries:

Attack Name: Invalid SSL Packet
Attack Information: SSL NULL termination certificate validation security bypass

VPN-1 NGX R65

How Can I Protect My Network?
1. In the SmartDefense tab, click Web Intelligence > HTTP Client Protections.
2. Select the following protection:

SSL NULL Termination Certificate Validation Security Bypass

3. In the configuration pane, under Settings > Mode, check Active.
4. Install policy on all modules.

How Do I Know if My Network is Under Attack?
SmartView Tracker will log the following entries:

Attack Name: Invalid SSL Packet
Attack Information: SSL NULL termination certificate validation security bypass

VPN-1 VSX NGX R65

How Do I Know if My Network is Under Attack?
SmartView Tracker will log the following entries:

Attack Name: Invalid SSL Packet
Attack Information: SSL NULL termination certificate validation security bypass

IPS-1 & IPS-1 NGX R65

How Can I Protect My Network?
1. In the IPS-1 Policy Manager, click on the Protection tab.
2. In the Protection tree, click Intelligence > SSL, and select the SSLv3/TLS Server Hello protection group.
3. Click SSL Certificate Man-In-The-Middle Attack (IPS-1 NGX R65 only).
4. In the configuration pane, under Settings, check Active.
5. Click on Install Policy.

How Do I Know if My Network is Under Attack?
Upon attack, the following entry will be logged:

Alert Name: SSLv3/TLS Server Hello
Description: SSL Certificate Man-In-The-Middle Attack

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