MS-ISAC CYBERSECURITY ADVISORIES

MS-ISAC ADVISORY NUMBER:
2016-184

DATE(S) ISSUED:
12/13/2016

SUBJECT:
A Vulnerability in Microsoft Uniscribe Could Allow for Remote Code Execution (MS16-147)

OVERVIEW:

A vulnerability exists in Windows Uniscribe that could allow for remote code execution. Uniscribe is a set of APIs that allow a high degree of control for fine typography and for processing complex scripts as well as supporting the display and editing of international text. Successful exploitation of this vulnerability could 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.

THREAT INTELLIGENCE:

There are no reports of these vulnerabilities being exploited in the wild.

SYSTEM AFFECTED:

· Microsoft Windows: Vista, 7, 8.1, RT 8.1, 10

· Microsoft Windows Server: 2008, 2008 R2, 2012, 2012 R2, 2016, Core

RISK:

Government:

· Large and medium government entities: High

· Small government entities: Medium

Businesses:

· Large and medium business entities: High

· Small business entities: Medium

Home users: Low

TECHNICAL SUMMARY:

A remote code execution vulnerability exists in Windows due to the way Windows Uniscribe handles objects in memory. To exploit this vulnerability, an attacker would need to convince a user to open a specially crafted document, or visit a maliciously crafted website. Successful exploitation of this vulnerability could 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 appropriate patches provided by Microsoft to vulnerable systems immediately after appropriate testing.
  • Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack.
  • Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.
  • Inform and educate users regarding the threats posed by hypertext links contained in emails or attachments, especially those from un-trusted sources.
  • Apply the Principle of Least Privilege to all systems and services.

REFERENCES:

Microsoft:

https://technet.microsoft.com/library/security/ms16-147

CVE:

http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-7274