[<prev] [next>] [day] [month] [year] [list]
Message-ID: <45A3EB43.7040605@idefense.com>
Date: Tue, 09 Jan 2007 14:21:39 -0500
From: iDefense Labs <labs-no-reply@...fense.com>
To: vulnwatch@...nwatch.org, full-disclosure@...ts.grok.org.uk,
bugtraq@...urityfocus.com
Subject: iDefense Security Advisory 01.09.07: Microsoft
Excel Long Palette Heap Overflow Vulnerability
Microsoft Excel Long Palette Heap Overflow Vulnerability
iDefense Security Advisory 01.09.07
http://labs.idefense.com/intelligence/vulnerabilities/
Jan 09, 2007
I. BACKGROUND
Microsoft Excel is the spreadsheet application from the Microsoft Office
System. More information is available at the following link:
http://office.microsoft.com/
II. DESCRIPTION
Remote exploitation of an heap-based buffer overflow vulnerability in
Microsoft Corp.'s Excel spreadsheet application format could allow an
attacker to execute arbitrary code in the context of the user who started
Excel.
The vulnerability specifically exists in the handling of the PALETTE
record in BIFF8 format spreadsheet files. By supplying a record with too
many entries, an exploitable buffer overflow condition can occur.
III. ANALYSIS
Successful exploitation of this vulnerability would allow an attacker to
execute arbitrary code in the context of the user who opened the document.
In order exploit this vulnerability, an attacker would need to convince the
target to open an Excel spreadsheet file. Likely attack vectors include
sending the file as an attachment in an email or linking to the file on a
website.
Systems with a default install of Office 2000 will open Office documents,
including Excel spreadsheet files, from websites without prompting the
user. This allows an attacker to exploit this vulnerability without user
interaction beyond visiting a website. Later versions of Office will not
open these documents automatically unless the user has chosen this
behavior.
IV. DETECTION
iDefense Labs have confirmed the existence of this vulnerability in
Microsoft Excel 2003 with all service packs and security updates. Previous
versions of Excel are also likely to be affected.
V. WORKAROUND
Do not follow links or open files from unknown sources or that you were not
expecting to receive.
VI. VENDOR RESPONSE
Microsoft has addressed this vulnerability with Microsoft Security Bulletin
MS07-002. A link to this bulletin can be found below.
http://www.microsoft.com/technet/security/bulletin/ms07-002.mspx
VII. CVE INFORMATION
The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2007-0031 to this issue. This is a candidate for inclusion in
the CVE list (http://cve.mitre.org), which standardizes names for
security problems.
VIII. DISCLOSURE TIMELINE
09/25/2006 Initial vendor notification
09/22/2006 Initial vendor response
01/09/2007 Coordinated public disclosure
IX. CREDIT
This vulnerability was discovered by Greg MacManus, iDefense Labs.
Get paid for vulnerability research
http://labs.idefense.com/methodology/vulnerability/vcp.php
Free tools, research and upcoming events
http://labs.idefense.com/
X. LEGAL NOTICES
Copyright © 2006 iDefense, Inc.
Permission is granted for the redistribution of this alert electronically.
It may not be edited in any way without the express written consent of
iDefense. If you wish to reprint the whole or any part of this alert in
any other medium other than electronically, please e-mail
customerservice@...fense.com for permission.
Disclaimer: The information in the advisory is believed to be accurate at
the time of publishing based on currently available information. Use of
the information constitutes acceptance for use in an AS IS condition.
There are no warranties with regard to this information. Neither the
author nor the publisher accepts any liability for any direct, indirect,
or consequential loss or damage arising from use of, or reliance on, this
information.
_______________________________________________
Full-Disclosure - We believe in it.
Charter: http://lists.grok.org.uk/full-disclosure-charter.html
Hosted and sponsored by Secunia - http://secunia.com/
Powered by blists - more mailing lists