Vulnerability Note VU#124460

Microsoft HTML Help Workshop buffer overflow

Original Release date: 13 Feb 2006 | Last revised: 14 Feb 2006


A buffer overflow in Microsoft HTML Help Workshop may allow a remote attacker to execute arbitrary code on a vulnerable system.


Microsoft HTML Help provides a standard help system for the Windows operating system. HTML Help Workshop is a component of the software development kit for HTML Help. A lack of validation on the Contents file field within HTML Help Workshop Project files headers may allow a stack-based buffer overflow to occur. Note that Microsoft HTML Help Workshop is not installed by default on any version of Microsoft Windows.

Exploit code for this vulnerability is publicly available.


By persuading a user to access a specially crafted HTML Help Workshop Project files (.hhp), a remote attacker may be able to execute arbitrary code.


We are unaware of a practical solution to this problem, however we suggest the following workaround to reduce the chances of exploitation:

Do not access HTML Help Workshop Project files from untrusted sources

Exploitation occurs if a user has the HTML Help SDK installed and accesses a specially crafted HTML Help Workshop Project file. By only accessing Help Workshop Project files from known and trusted sources, the chances of exploitation are reduced.

Systems Affected (Learn More)

VendorStatusDate NotifiedDate Updated
Microsoft CorporationAffected-13 Feb 2006
If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

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



This vulnerability was reported by bratax.

This document was written by Jeff Gennari.

Other Information

  • CVE IDs: CVE-2006-0564
  • Date Public: 06 Feb 2006
  • Date First Published: 13 Feb 2006
  • Date Last Updated: 14 Feb 2006
  • Severity Metric: 17.08
  • Document Revision: 51


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