Check Point Advisories

Microsoft Office VBA Module Stream Use after Free

Vulnerability
Protection

Check Point Reference:	CPAI-2012-109
Date Published:	26 Mar 2012
Severity:	High
Last Updated:	Monday 26 March, 2012
Source:
Protection Provided by:	Security Gateway R81, R80, R77, R75
Who is Vulnerable?
Vulnerability Description	A use-after-free vulnerability has been reported in Microsoft Excel. The vulnerability is due to an error in Excel while handling malformed VBA module streams in Excel files. A remote attacker may exploit this issue by enticing a user to open a specially crafted Excel file and then perform certain actions. Successful exploitation will allow an attacker to execute arbitrary code in the security context of the logged-on user.

Protection Overview

This protection will detect and block malformed Excel files.

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 Microsoft Office VBA Module Stream Use after Free 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: Content Protection Violation.
Attack Information: Microsoft Office VBA module stream use after free