Microsoft Security Bulletin (MS00-056)
Patch Available for "Microsoft Office HTML Object Tag" Vulnerability
Originally posted: August 09, 2000
Microsoft has released a patch that eliminates a security
vulnerability in certain Microsoft(r) Office 2000 products. The
vulnerability could allow a user to construct a HyperText Markup
Language (HTML) file that, when read, would crash a Microsoft Office
2000 application or potentially run arbitrary or malicious code.
Frequently asked questions regarding this vulnerability and
the patch can be found at
Microsoft Office 2000 applications are capable of reading HTML files
saved as Office documents. A malformed data object tag embedded in
one of these documents could cause the Office application to crash
and allow arbitrary code to be executed.
In order for this behavior to occur, a malicious user would need to
entice a user into opening the malformed Office document. Word 2000
users can protect themselves from opening malformed HTML documents
within Word by disabling "Confirm conversion at Open" from the
Tools-Options-General tab. In addition, Outlook users who have
applied the Outlook Security Update will be prompted before opening
web hosted or mail-borne Office documents.
Affected Software Versions
- Microsoft Word 2000
- Microsoft Excel 2000
- Microsoft PowerPoint 2000
(These products ship as part of the Office 2000 suite and as
Note: Previous versions of these products are not affected by this
Note: Office 2000 products other than those specifically listed above
are not affected by this vulnerability.
- Microsoft Word 2000, Excel 2000, PowerPoint 2000:
Note: Office 2000 SR-1 is required before this patch can be applied.
Note: Additional security patches are available at the Microsoft
Please see the following references for more information related to
- Frequently Asked Questions: Microsoft Security Bulletin MS00-056,
- Microsoft Knowledge Base (KB) article Q269880,
- Microsoft TechNet Security website,
Obtaining Support on this Issue
This is a fully supported patch. Information on contacting Microsoft
Product Support Services is available at
Microsoft thanks Jesper M. Johansson for reporting this issue to us
and working with us to protect customers.
- August 09, 2000: Bulletin Created.
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