Update Microsoft Office to address multiple vulnerabilities

This information was sent to IT staff groups on August 12, 2015.

This message is intended for U-M IT staff who are responsible for managing university machines that have Microsoft Office installed.

Summary

Multiple vulnerabilities have been discovered in Microsoft Office. The most severe of these could allow remote code execution if a user opens a specially crafted Microsoft Office file. An attacker who successfully exploits the vulnerabilities could run arbitrary code in the context of the current user. Microsoft has reported that one vulnerability has been exploited in the wild. Patches are available to address the vulnerabilities and should be applied as soon as possible after appropriate testing.

Affected Systems

  • Microsoft Office 2007
  • Microsoft Office 2010
  • Microsoft Office 2013
  • Microsoft Office 2013 RT
  • Microsoft Office for Mac 2011
  • Microsoft Office for Mac 2016
  • Microsoft Office Compatibility Pack
  • Microsoft Word Viewer
  • Microsoft Automation Services on Microsoft SharePoint Server 2010
  • Microsoft Automation Services on Microsoft SharePoint Server 2013
  • Microsoft Word Web Apps 2010
  • Microsoft Office Web Apps Server 2013

Action Items

  • 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.

Technical Details

Eight vulnerabilities have been reported in Microsoft Office, one of which has been publicly disclosed. Seven of these vulnerabilities can be triggered by opening a specially crafted file and can be exploited via email or through the web. In the email-based scenario, the user would have to open the specially crafted file as an email attachment. In the web based scenario, a user would have to open the specially crafted file that is hosted on a website. When the user opens the file, the attacker's supplied code will execute. The eighth vulnerability requires an attacker to leverage a separate vulnerability and execute code in Internet Explorer.

  • Five remote code execution vulnerabilities exist in the way Office handles objects in memory (CVE-2015-1642, CVE-2015-2467, CVE-2015-2468, CVE-2015-2469, CVE-2015-2477).
  • A remote code execution vulnerability exists in Microsoft Office software when the Office software fails to properly validate templates (CVE-2015-2466).
  • A remote code execution vulnerability exists when Office decreases an integer value beyond its intended minimum value (CVE-2015-2470).
  • An information disclosure vulnerability exists in Microsoft Windows, Internet Explorer, and Microsoft Office when files at a medium integrity level become accessible to Internet Explorer running in Enhanced Protection Mode (EPM).To exploit this vulnerability, an attacker would first need to leverage another vulnerability and execute code in Internet Explorer with EPM, and then execute Excel, Notepad, PowerPoint, Visio, or Word using an unsafe command line parameter. (CVE-2015-2423) This vulnerability has been publicly disclosed.

Information for Users

MiWorkspace and U-M Health System (UMHS) Core-Image workstations will be patched as soon as possible. If you have Microsoft Office installed on your own computer that is not managed by the university, update to the latest version as soon as possible. It is best to set Office to check for updates automatically.

In general, the best protection for your devices is this: keep your software and apps up-to-date, do not click suspicious links in email, do not open email attachments unless you are expecting them and trust the person who sent them, and only use secure, trusted networks. For more information, see Spam, Phishing, and Suspicious Email, Instructions for Securing Your Devices and Data, and Use a Secure Internet Connection.

Questions, Concerns, Reports

Please contact [email protected].

References