iDefense Security Advisory 04.17.08
http://labs.idefense.com/intelligence/vulnerabilities/
Apr 17, 2008

I. BACKGROUND

OpenOffice is an open-source desktop office suite for many of today's
popular operating systems. One of the file formats that OpenOffice
supports is Quattro Pro (QPRO). This format is used by Corel's
QuattroPro spreadsheet application. More information is available from
the following URL.

http://www.openoffice.org/

II. DESCRIPTION

Remote exploitation of multiple buffer overflow vulnerabilities in
OpenOffice, as included in various vendors' operating system
distributions, allows attackers to execute arbitrary code with the
privileges of the logged in user.

The first vulnerability occurs when parsing "Attribute" records from the
file. Due to a lack of bounds checking during a loop that reads these
records, an attacker can trigger a heap overflow by inserting more than
256 records.

The second vulnerability is nearly identical to the first one, but
involves the "Font Description" record instead of the "Attribute"
record.

III. ANALYSIS

Exploitation of these vulnerabilities results in the execution of
arbitrary code with the privileges of the user opening the file. In
order to exploit this vulnerability, an attacker must persuade a user
to open a malicious file.

IV. DETECTION

iDefense confirmed the existence of these vulnerabilities in OpenOffice
version 2.3. Other versions may also be affected.

V. WORKAROUND

Renaming the shared library that contains the vulnerable code will
prevent OpenOffice from opening QPRO files. On Fedora Core 7, the
library can be found at:

  /usr/lib/openoffice.org/program/libsc680li.so

Renaming this file to libsc680li.so.bak will prevent it from being
loaded. In addition to preventing the use of QPRO files, this also
prevents users from opening various other file formats.

VI. VENDOR RESPONSE

The OpenOffice.org team has addressed these vulnerabilities with the
release of version 2.4. For more information, consult the OOo Security
Bulletin at the following URL.

http://www.openoffice.org/security/cves/CVE-2007-5745.html

VII. CVE INFORMATION

The Common Vulnerabilities and Exposures (CVE) project has assigned the
name CVE-2007-5745 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

10/29/2007  Initial vendor notification
10/30/2007  Initial vendor response
04/17/2008  Coordinated public disclosure

IX. CREDIT

These vulnerabilities were discovered by Sean Larsson (iDefense Labs)
and an anonymous researcher.

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 © 2008 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@idefense.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.