Vulnerability Note VU#619281

Windows font library file buffer overflow

Overview

Microsoft Windows contains a buffer overflow vulnerability in the handling of font library files, which may allow a remote, unauthenticated attacker to execute arbitrary code with kernel privileges.

I. Description

Microsoft Windows supports a variety of font formats. One of which is the font library file format, which have the file extension of .FON. Rendering of font library files takes place in the Windows GDI (Graphics Device Interface), which is part of the Windows kernel-mode driver win32k.sys. Microsoft Windows contains a buffer overflow in the handling of font library files.

II. Impact

By convincing a user to open a specially-crafted font library file, a remote, unauthenticated attacker could execute arbitrary code with kernel privileges. A local use could also gain elevated privileges.

III. Solution

Apply an update

This issue is addressed in Microsoft Security Bulletin MS11-077.

Vendor Information

Vendor	Status	Date Notified	Date Updated
Microsoft Corporation	Affected	2011-06-10	2011-10-11

References

http://technet.microsoft.com/en-us/security/bulletin/ms11-077
http://exploitshop.wordpress.com/2011/10/12/ms11-077-vulnerabilities-in-windows-kernel-mode-drivers-could-allow-remote-code-execution-2567053/

Credit

This issue was reported by Will Dormann of the CERT/CC.

This document was written by Will Dormann.

Other Information

Date Public:	2011-10-11
Date First Published:	2011-10-11
Date Last Updated:	2011-10-13
CERT Advisory:
CVE-ID(s):	CVE-2011-2003
NVD-ID(s):	CVE-2011-2003
US-CERT Technical Alerts:	TA11-284A
Severity Metric:	9.49
Document Revision:	12