Published: September 13, 2016 | Updated: September 22, 2016
Version: 2.0
Executive Summary
This security update resolves vulnerabilities in Microsoft Office. The most severe of the vulnerabilities could allow remote code execution if a user opens a specially crafted Microsoft Office file. An attacker who successfully exploited the vulnerabilities could run arbitrary code in the context of the current user. Customers whose accounts are configured to have fewer user rights on the system could be less impacted than those who operate with administrative user rights.
For more information, see the Affected Software and Vulnerability Severity Ratings section.
The security update addresses the vulnerabilities by correcting how:
Microsoft Office saves documents.
Click-to-Run components handle memory addresses.
affected versions of Office and Office components handle objects in memory.
Microsoft Outlook determines the end of MIME messages.
For more information about the vulnerabilities, see the Vulnerability Information section.
Affected Software and Vulnerability Severity Ratings
The following software versions or editions are affected. Versions or editions that are not listed are either past their support life cycle or are not affected. To determine the support life cycle for your software version or edition, see Microsoft Support Lifecycle.
The following severity ratings assume the potential maximum impact of the vulnerability. For information regarding the likelihood, within 30 days of this security bulletin's release, of the exploitability of the vulnerability in relation to its severity rating and security impact, please see the Exploitability Index in the September bulletin summary.
[2]This reference is for the Click-to-Run (C2R) version only. For more information and the current Click-to-Run version number, see Update Office 2013 or Office 365.
*The Updates Replaced column shows only the latest update in a chain of superseded updates. For a comprehensive list of updates replaced, go to the Microsoft Update Catalog, search for the update number, and then view update details (updates replaced information is on the Package Details tab).
[2]This reference is for the Click-to-Run (C2R) version only. For more information and the current Click-to-Run version number, see Update Office 2013 or Office 365.
*The Updates Replaced column shows only the latest update in a chain of superseded updates. For a comprehensive list of updates replaced, go to the Microsoft Update Catalog, search for the update number, and then view update details (updates replaced information is on the Package Details tab).
*The Updates Replaced column shows only the latest update in a chain of superseded updates. For a comprehensive list of updates replaced, go to the Microsoft Update Catalog, search for the update KB number, and then view update details (updates replaced information is on the Package Details tab).
Update FAQ
I am being offered this update for software that is not specifically indicated as being affected in the Affected Software and Vulnerability Severity Ratings table. Why am I being offered this update?
When updates address vulnerable code that exists in a component that is shared between multiple Microsoft Office products or shared between multiple versions of the same Microsoft Office product, the update is considered to be applicable to all supported products and versions that contain the vulnerable component.
For example, when an update applies to Microsoft Office 2007 products, only Microsoft Office 2007 may be specifically listed in the Affected Software table. However, the update could apply to Microsoft Word 2007, Microsoft Excel 2007, Microsoft Visio 2007, Microsoft Compatibility Pack, Microsoft Excel Viewer, or any other Microsoft Office 2007 product that is not specifically listed in the Affected Software table. Furthermore, when an update applies to Microsoft Office 2010 products, only Microsoft Office 2010 may be specifically listed in the Affected Software table. However, the update could apply to Microsoft Word 2010, Microsoft Excel 2010, Microsoft Visio 2010, Microsoft Visio Viewer, or any other Microsoft Office 2010 product that is not specifically listed in the Affected Software table.
For more information on this behavior and recommended actions, see Microsoft Knowledge Base Article 830335. For a list of Microsoft Office products that an update may apply to, refer to the Microsoft Knowledge Base Article associated with the specific update.
Vulnerability Information
Microsoft APP-V ASLR Bypass - CVE-2016-0137
An information disclosure vulnerability exists in the way that the Click-to-Run (C2R) components handle objects in memory, which could lead to an Address Space Layout Randomization (ASLR) bypass.
An attacker who successfully exploited the information disclosure vulnerability could use the obtained information to bypass the ASLR security mechanism in Windows, which helps protect users from a broad class of vulnerabilities. The ASLR bypass by itself does not allow arbitrary code execution; however, an attacker could use the ASLR bypass in conjunction with another vulnerability, such as a remote code execution vulnerability, that could leverage the ASLR bypass to run arbitrary code.
To exploit the ASLR bypass, an attacker would have to log on to an affected system and run a specially crafted application. Workstations are primarily vulnerable to the potential ASLR bypass.
The security update addresses the ASLR bypass by correcting how C2R components handle memory addresses.
The following table contains links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list:
Microsoft has not identified any mitigating factors for this bypass condition.
Workarounds
Microsoft has not identified any workarounds for this bypass condition.
Microsoft Information Disclosure Vulnerability - CVE-2016-0141
An information disclosure vulnerability exists when Visual Basic macros in Office improperly exports a user’s private key from the certificate store while saving a document. An attacker who successfully exploited the vulnerability could potentially gain access to the user’s private key.
The attacker would have to use another vulnerability, or employ a social engineering technique, to obtain the saved document from the user.
The security update addresses the vulnerability by correcting how Microsoft Office saves documents.
The following table contains links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list:
Microsoft has not identified any mitigating factors for this vulnerability.
Workarounds
Microsoft has not identified any workarounds for this vulnerability.
Multiple Microsoft Office Memory Corruption Vulnerabilities
Multiple remote code execution vulnerabilities exist in Microsoft Office software when the Office software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerabilities could run arbitrary code in the context of the current user. If the current user is logged on with administrative user rights, an attacker could take control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.
Exploitation of the vulnerabilities requires that a user open a specially crafted file with an affected version of Microsoft Office software. In an email attack scenario an attacker could exploit the vulnerabilities by sending the specially crafted file to the user and convincing the user to open the file. In a web-based attack scenario an attacker could host a website (or leverage a compromised website that accepts or hosts user-provided content) that contains a specially crafted file that is designed to exploit the vulnerabilities. An attacker would have no way to force users to visit the website. Instead, an attacker would have to convince users to click a link, typically by way of an enticement in an email or Instant Messenger message, and then convince them to open the specially crafted file.
Note that where the severity is indicated as Critical in the Affected Software and Vulnerability Severity Ratings table, the Preview Pane is an attack vector for CVE-2016-3357.
The security update addresses the vulnerabilities by correcting how Microsoft Office handles objects in memory.
The following table contains links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list:
Microsoft has not identified any mitigating factors for these vulnerabilities.
Workarounds
Microsoft has not identified any workarounds for these vulnerabilities.
Microsoft Office Spoofing Vulnerability - CVE-2016-3366
A spoofing vulnerability exists when Microsoft Outlook does not strictly adhere to RFC2046, and improperly identifies the end of a MIME attachment. An improper MIME attachment ending may cause antivirus or antispam scanning to not work as intended.
To exploit the vulnerability, an attacker could send a specially crafted email attachment to a user in an attempt to launch a social engineering attack, such as phishing.
The security update addresses the vulnerability by correcting how Outlook determines the end of MIME messages.
The following table contains links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list:
Microsoft has not identified any mitigating factors for this vulnerability.
Workarounds
Microsoft has not identified any workarounds for this vulnerability.
Security Update Deployment
For Security Update Deployment information, see the Microsoft Knowledge Base article referenced in the Executive Summary.
Acknowledgments
Microsoft recognizes the efforts of those in the security community who help us protect customers through coordinated vulnerability disclosure. See Acknowledgments for more information.
Disclaimer
The information provided in the Microsoft Knowledge Base is provided "as is" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.
Revisions
V1.0 (September 13, 2016): Bulletin published.
V2.0 (September 22, 2016): Bulletin revised to announce the availability of the 14.6.8 update for Microsoft Office for Mac 2011 (3186805) and the 15.25 update for Microsoft Office 2016 for Mac (3186807). Customers running affected Mac software should install the appropriate update for their product to be protected from the vulnerabilities discussed in this bulletin. Customers running other Microsoft Office software do not need to take any action. See Microsoft Knowledge Base Article 3186805 and Microsoft Knowledge Base Article 3186807 for more information and download links.
This module examines how Microsoft Defender for Office 365 extends EOP protection through various tools, including Safe Attachments, Safe Links, spoofed intelligence, spam filtering policies, and the Tenant Allow/Block List.