Update Protection against Microsoft Excel SST Record Integer Overflow Vulnerability (MS09-021)

Vulnerability
Protection

Check Point Reference:	CPAI-2009-148
Date Published:
Severity:
Source:	Microsoft Security Bulletin MS09-021
Industry Reference(s):	CVE-2009-0561
Protection Provided by:	Security Gateway R70 IPS-1 IPS-1 IPS-1 NGX R65
Who is Vulnerable? Microsoft Office Excel 2000 SP3 Microsoft Office Excel 2002 SP3 Microsoft Office Excel 2003 SP3 Microsoft Office Excel 2007 SP1 Microsoft Office Excel 2007 SP2 Microsoft Office for Mac 2004 Microsoft Office for Mac 2008 Microsoft Office Excel Viewer 2003 SP3 Microsoft Office Excel Viewer Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint 2007 File Formats Microsoft Works 8.5 Mocrosoft Works 9 Microsoft Office SharePoint Server 2007
Vulnerability Description A remote code execution vulnerability has been identified in the Microsoft Excel. Microsoft Excel is a popular spreadsheet application. A remote attacker could exploit this issue via a malformed Excel file. Successful exploitation of this vulnerability may allow execution of arbitrary code on a target system.

Update/Patch Available
Apply patches:
Microsoft Security Bulletin MS09-021

Vulnerability Details
The flaw is due to a memory corruption error in Microsoft Excel when loading specially crafted Excel files that include a malformed record object. The vulnerability occurs in the parsing of a malformed SST record. A remote attacker could trigger this flaw by convincing a victim to open a malformed Excel spreadsheet file. Successful exploitation of this issue may allow the attacker to take complete control of an affected system.

Protection Overview
This protection will detect and block the transferring of malformed Excel files over HTTP.

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, 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 Excel SST Record Integer Overflow (MS09-021) 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 Excel SST record integer overflow (MS09-021)

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 CVE-2009-0561 Microsoft Excel Record Integer Overflow (MS09-021) - (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: CVE-2009-0561 Microsoft Excel Record Integer Overflow (MS09-021)

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