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Microsoft Jet Engine stack buffer overflow

Vulnerability Note VU#936529

Original Release Date: 2008-03-22 | Last Revised: 2008-05-13

Overview

The Microsoft Jet Engine contains a stack buffer overflow, which can allow a remote, unauthenticated attacker to execute arbitrary code on a vulnerable system.

Description

Microsoft Jet, or Joint Engine Technology, is a database engine that is used by several Microsoft products, including Access and Visual Basic. A Microsoft Access database uses the .MDB file extension by default. The Microsoft Jet Engine contains a stack buffer overflow in the handling of specially crafted database files.

Microsoft Word can link to Jet databases. In some cases, the database can be opened without prompting the user. This can allow Microsoft Word documents to be used as an attack vector for this vulnerability. Microsoft Outlook can also be used as an attack vector by either opening a specially crafted email message or by viewing such a message in the preview pane.

Impact

By convincing a user to open a specially crafted Word document or Jet database, such as a Microsoft Access .MDB file, a remote, unauthenticated attacker may be able to execute arbitrary code on a vulnerable system.

Solution

Apply an update
This issue is addressed in Microsoft Security Bulletin MS08-028.

Block MDB files from being processed through your mail infrastructure


To detect Jet files that have possibly been renamed to another file type, search for files with any of the following 15-byte signatures at location 0x4 (no quotes):

"Jet System DB  "
"Standard Jet DB"
"Temp Jet DB    "
"MSISAM Database"
Configure Microsoft Outlook to view and edit email messages in plain text

According to Microsoft, this can be accomplished in the following ways:

Manual (User Interaction)
Enterprise Users follow these steps to disable the Outlook feature to use Word as mail editor:

    1. Restart the machine.
    2. Open Outlook
    3. Click Tools, click Options, and then click the Mail Format tab.
    4. Clear the Use Microsoft Word to edit e-mail messages check box.
    5. Clear the Use Microsoft Word to read Rich Text e-mail messages box.
    6. Exit Outlook.
    7. Restart the machine.

    Impact of Workaround: Users will not be able to use Word as their e-mail editor or use Rich Text to read their e-mail
    Using Group Policy
    Domain administrators can use Group Policy to disable Word as the users e-mail editor. You do not have to restart the computer to implement this mitigation.
    For information on using registry keys with a Group Policy see Using Administrative Template Files with Registry-Based Group Policy and Distributing Registry Changes.

    Disable WordMail in Word 2003
      Windows Registry Editor Version 5.00

      [HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\Options\Mail]
      "EditorPreference"=dword:00020000
      "UseWordMail"=dword:00000000

    Disable WordMail in Word 2002
      Windows Registry Editor Version 5.00

      [HKEY_CURRENT_USER\Software\Microsoft\Office\10.0\Outlook\Options\Mail]
      "EditorPreference"=dword:00020000
      "UseWordMail"=dword:00000000

    Impact of Workaround: Users will not be able to use Word as their e-mail editor or use Rich Text by default to read their e-mail.
    Restrict the Microsoft Jet Database Engine from running

    To implement the workaround, enter the following command at a command prompt:

    echo y| cacls "%SystemRoot%\system32\msjet40.dll" /E /P everyone:N

    Vendor Information

    936529
    Expand all

    Microsoft Corporation

    Notified:  November 16, 2007 Updated:  May 13, 2008

    Status

      Vulnerable

    Vendor Statement

    No statement is currently available from the vendor regarding this vulnerability.

    Vendor Information

    The vendor has not provided us with any further information regarding this vulnerability.

    Addendum

    This issue is addressed in Microsoft Security Bulletin MS08-028.

    If you have feedback, comments, or additional information about this vulnerability, please send us email.


    CVSS Metrics

    Group Score Vector
    Base N/A N/A
    Temporal N/A N/A
    Environmental N/A

    References

    Credit

    This vulnerability was publicly reported by cocoruder.

    This document was written by Will Dormann.

    Other Information

    CVE IDs: CVE-2007-6026, CVE-2008-1092
    Severity Metric: 58.22
    Date Public: 2007-11-16
    Date First Published: 2008-03-22
    Date Last Updated: 2008-05-13 17:32 UTC
    Document Revision: 36

    Sponsored by the Department of Homeland Security Office of Cybersecurity and Communications.