ITS ADVISORY NUMBER:
2012-002

DATE(S) ISSUED:
01/10/2012

SUBJECT:
Vulnerability in Windows Could Allow Remote Code Execution (MS12-005)

OVERVIEW:

A vulnerability has been discovered in a component of Microsoft Windows. Exploitation may occur if a user opens a specially crafted Microsoft Office file. Successful exploitation will result in an attacker gaining the same privileges as the logged on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.

SYSTEMS AFFECTED:

• Microsoft Windows XP
• Microsoft Vista
• Microsoft Windows 7
• Microsoft Windows Server 2003
• Microsoft Windows Server 2008

RISK:
Government:

• Large and medium government entities: High
• Small government entities: High

Businesses:

• Large and medium business entities: High
• Small business entities: High

Home users: High

DESCRIPTION:
A vulnerability exists in the Windows Packager component in Microsoft Windows. This vulnerability occurs when the Windows Packager fails to properly handle a Microsoft Office file embedded with a specially crafted ClickOnce application. This vulnerability is caused due to ClickOnce application files not being included in the Windows Packager's list of unsafe file types. 

ClickOnce is a Microsoft technology, which allows programmers to create self-updating Windows-based applications. A ClickOnce application can consist of the following: Windows Presentation Foundation (.xbap), Windows Forms (.exe), console application (.exe), or Office solution (.dll).  Very little user interaction is needed to install these applications. ClickOnce applications can be published in three different ways: from a web page, from a network file share, or from media such as a CD-ROM.

Successful exploitation may result in an attacker gaining the same privileges as the logged on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. 

RECOMMENDATIONS:
We recommend the following actions be taken:

• Apply the appropriate patch provided by Microsoft to vulnerable systems immediately after appropriate testing.
• Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.
• Remind users not to open e-mail attachments from unknown or un-trusted sources.
• Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack.

REFERENCES:
Microsoft:
http://technet.microsoft.com/en-us/security/bulletin/ms12-005

CVE:
http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2012-0013

Security Focus:
http://www.securityfocus.com/bid/51284