Vulnerability Note VU#316553

Microsoft Windows TrueType font parsing vulnerability

Original Release date: 04 Nov 2011 | Last revised: 19 Dec 2011


A vulnerability in the Microsoft Windows TrueType font parsing component could allow an attacker to run arbitrary code in kernel mode. This vulnerability is reportedly being exploited by malicious software in the wild known as Duqu.


The Microsoft Windows kernel includes a driver (win32k.sys) that handles a variety of graphics processing tasks, including the processing of TrueType fonts. A vulnerability exists in the way this driver handles certain embedded TrueType fonts. This vulnerability could allow an attacker to execute code with elevated privileges on the affected system.

A remote attacker could exploit this vulnerability by embedding a specially crafted font in a document attached to an email message or including the crafted font in a web page.


An attacker may be able to run arbitrary code in kernel mode, resulting in complete system compromise. Secondary impacts include, but are not limited to, installation of programs; viewing, changing, or deleting data; or the creation of new system accounts with full privileges.


Apply an update

Microsoft has addressed this issue in Microsoft Security Bulletin MS11-087. Users may also wish to consider applying the following workaround:

Deny access to T2EMBED.DLL

Microsoft has published a workaround for this issue in Microsoft Security Advisory (2639658), which recommends denying access to T2EMBED.DLL. Users are encouraged to review this advisory and consider applying the workaround that it describes. Additionally, Microsoft Knowledge Base Article 2639658 contains Microsoft Fix it 50792 and Microsoft Fix it 50793 to help users apply this workaround.

Vendor Information (Learn More)

VendorStatusDate NotifiedDate Updated
Microsoft CorporationAffected02 Nov 201119 Dec 2011
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 document was written by Chad R Dougherty.

Other Information

  • CVE IDs: CVE-2011-3402
  • Date Public: 02 Nov 2011
  • Date First Published: 04 Nov 2011
  • Date Last Updated: 19 Dec 2011
  • Severity Metric: 26.73
  • Document Revision: 14


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