Workaround for Microsoft Excel Document Malformed Formula Memory Corruption Vulnerability (MS09-067)

Vulnerability
Protection

Check Point Reference:	SBP-2009-22
Date Published:
Severity:
Last Updated:
Source:	Microsoft Security Bulletin MS09-067
Industry Reference(s):	CVE-2009-3131 CVE-2010-1251 CVE-2010-1252
Protection Provided by:	Security Gateway R70 VPN-1 NGX R65 VSX NGX R65 IPS-1 IPS-1 IPS-1 NGX R65
Who is Vulnerable? Microsoft Office Excel 2002 SP3 Microsoft Office Excel 2003 SP3 Microsoft Office Excel 2007 SP1 Microsoft Office Excel 2007 SP2 Microsoft Office for Mac Microsoft Office 2004 for Mac Microsoft Office 2008 for Mac Open XML File Format Converter for Mac Microsoft Office Excel Viewer 2003 SP3 Microsoft Office Excel Viewer SP1 Microsoft Office Excel Viewer SP2 Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP1 Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats SP2
Vulnerability Description A remote code execution vulnerability has been identified in Microsoft Excel. Microsoft Excel is a popular spreadsheet application. A remote attacker could exploit this issue via an Excel file in legacy format. Successful exploitation of this vulnerability may allow execution of arbitrary code on a target system.

Update/Patch Available
Apply patches:
Microsoft Security Bulletin MS09-067

Vulnerability Details
The vulnerability is due to an error in Microsoft Office Excel that fails to properly parse Excel spreadsheet files that contain a specially crafted formula. A remote attacker could trigger this flaw by convincing a victim to open a specially crafted Excel spreadsheet file in legacy format. Successful exploitation of this issue may corrupt system memory, allowing execution of arbitrary code on a vulnerable system.

Protection Overview
This protection detects and blocks the transferring of legacy Office Excel files over HTTP.

Since the protection offered in this advisory may degrade performance and block access to legitimate files, users are advised to use this protection as a workaround till all systems are patched.

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 > Application Intelligence > Content Protection.
2. In the right pane, double-click the Microsoft Office Excel Legacy Files 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: Content Protection Violation
Attack Information: Microsoft Office Excel legacy file

VPN-1 NGX R65 & VPN-1 VSX NGX R65

How Can I Protect My Network?
1. In the SmartDefense tab, click Application Intelligence > Content Protection.
2. Select the following protection:

Microsoft Office Excel Legacy Files

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

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 Application Intelligence > Badfiles, and select the Microsoft Office Parser protection group.
3. Click Microsoft Office Excel Formula Parsing Memory Corruption (MS09-067) (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 entries will be logged:

Alert Name: Vulnerability in MS-Office file
Description: Microsoft Office Excel Formula Parsing Memory Corruption (MS09-067)

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