Vulnerability Note VU#619281

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.

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.

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.

Solution

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

Vendor Information (Learn More)

Vendor	Status	Date Notified	Date Updated
Microsoft Corporation	Affected	10 Jun 2011	11 Oct 2011

If you are a vendor and your product is affected, let us know.

CVSS Metrics (Learn More)

Group	Score	Vector
Base	9.0	AV:N/AC:M/Au:N/C:C/I:C/A:P
Temporal	7.0	E:POC/RL:OF/RC:C
Environmental	7.0	CDP:ND/TD:ND/CR:ND/IR:ND/AR:ND

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

• CVE IDs: CVE-2011-2003
• US-CERT Alert: TA11-284A
• Date Public: 11 Oct 2011
• Date First Published: 11 Oct 2011
• Date Last Updated: 28 Mar 2012
• Severity Metric: 9.49
• Document Revision: 15