NSFOCUS Security Advisory (SA2006-04)

Microsoft Office GIF Filter Buffer Overflow Vulnerability

Release Date: 2006-07-12

CVE ID: CVE-2006-0007

http://www.nsfocus.com/english/homepage/research/0604.htm

Affected systems & software
===================
Microsoft Office 2000
Microsoft Office XP
Microsoft Office 2003

Unaffected systems & software
===================


Summary
=========

NSFocus Security Team discovered a buffer overflow vulnerability in Microsoft Office
GIF filter, which could allow attackers to run arbitrary code via a carefully crafted
GIF image. 

Description
============

GIFIMP32.FLT is a GIF image filter shipped with Microsoft Office, which is 
installed by default in %CommonProgramFiles%\Microsoft Shared\Grphflt\GIFIMP32.FLT. 

GIFIMP32.FLT contains a buffer overflow vulnerability in the handling of some
malformed GIF images, which allows attackers to run arbitrary code. Any application
that calls GIFIMP32.FLT is affected by this vulnerability. For example, mspaint.exe
will call the filter automatically when opening files in .gif format, if Microsoft
Office is installed. Attackers could gain control over a system by alluring users to
open a malicious GIF image.

Workaround
=============

1. Do not open any GIF image from untrusted sources. 
2. Temporarily remove GIFIMP32.FLT. 
    
Vendor Status
==============

2005.05.27  Informed the vendor
2005.06.02  Vendor confirmed the vulnerability
2006.07.11  Microsoft has released a security bulletin (MS06-039) and related 
            patches. 
            
For more details about the security bulletin, please refer to: 
http://www.microsoft.com/technet/security/bulletin/MS06-039.mspx

Additional Information
========================

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2006-0007 to this issue. This is a candidate for inclusion in the 
CVE list (http://cve.mitre.org), which standardizes names for security problems.
Candidates may change significantly before they become official CVE entries.

Acknowledgment
===============

Yu Yang of NSFocus Security Team found the vulnerability.

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==========
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Copyright 1999-2006 NSFOCUS. All Rights Reserved. Terms of use.


NSFOCUS Security Team <security@nsfocus.com>
NSFOCUS INFORMATION TECHNOLOGY CO.,LTD
(http://www.nsfocus.com)

PGP Key: http://www.nsfocus.com/homepage/research/pgpkey.asc
Key fingerprint = F8F2 F5D1 EF74 E08C 02FE 1B90 D7BF 7877 C6A6 F6DA