Microsoft Security Bulletin MS15-081 - Critical

Vulnerabilities in Microsoft Office Could Allow Remote Code Execution (3080790)

Published: August 11, 2015 | Updated: October 13, 2015

Version: 3.0

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 Office handles files in memory
  • Improving, in conjunction with the updates for Internet Explorer and Microsoft Windows, how Microsoft Office programs are executed from Internet Explorer
  • Correcting how Office validates Office templates prior to use
  • Correcting how Office handles integer bounds checking

For more information about the vulnerabilities, see the Vulnerability Information section.

For more information about this update, see Microsoft Knowledge Base Article 3080790

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 August bulletin summary.  

Microsoft Office Software

Vulnerability Severity Rating and Maximum Security Impact by Affected Software
Affected Software Microsoft Office Memory Corruption Vulnerability - CVE-2015-1642 Unsafe Command Line Parameter Passing Vulnerability - CVE-2015-2423 Microsoft Office Remote Code Execution Vulnerability - CVE-2015-2466 Microsoft Office Memory Corruption Vulnerability - CVE-2015-2467 Microsoft Office Memory Corruption Vulnerability - CVE-2015-2468 Microsoft Office Memory Corruption Vulnerability - CVE-2015-2469 Microsoft Office Integer Underflow Vulnerability - CVE-2015-2470 Microsoft Office Memory Corruption Vulnerability - CVE-2015-2477 Updates Replaced
Microsoft Office 2007
Microsoft Office 2007 Service Pack 3 (2687409) ImportantRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 2596744 in MS12-046
Microsoft Office 2007 Service Pack 3 (3054888) Not applicable Not applicable CriticalRemote Code Execution ImportantRemote Code Execution Not applicable Not applicable Not applicable Not applicable 2965282 in MS15-046
Microsoft Office 2007 Service Pack 3 (2596650) Not applicable Not applicable CriticalRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Office 2007 Service Pack 3 (2837610) Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution ImportantRemote Code Execution 2597973 in MS13-072
Microsoft Excel 2007 Service Pack 3 (3054992) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 2965281 in MS15-070
Microsoft PowerPoint 2007 Service Pack 3 (3055051) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 2965283 in MS15-070
Microsoft Visio 2007 Service Pack 3 (2965280) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 2596595 in MS13-044
Microsoft Word 2007 Service Pack 3 (3055052) Not applicable ImportantInformation Disclosure Not applicable Not applicable ImportantRemote Code Execution ImportantRemote Code Execution Not applicable Not applicable 3054996 in MS15-070
Microsoft Office 2010
Microsoft Office 2010 Service Pack 2 (32-bit editions) (2965310) ImportantRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 2598243 in MS12-046
Microsoft Office 2010 Service Pack 2 (64-bit editions) (2965310) ImportantRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 2598243 in MS12-046
Microsoft Office 2010 Service Pack 2 (32-bit editions) (3055037) Not applicable ImportantInformation Disclosure Not applicable Not applicable ImportantRemote Code Execution ImportantRemote Code Execution Not applicable Not applicable 3054971 in MS15-070
Microsoft Office 2010 Service Pack 2 (64-bit editions) (3055037) Not applicable ImportantInformation Disclosure Not applicable Not applicable ImportantRemote Code Execution ImportantRemote Code Execution Not applicable Not applicable 3054971 in MS15-070
Microsoft Office 2010 Service Pack 2 (32-bit editions) (2553313) Not applicable Not applicable CriticalRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Office 2010 Service Pack 2 (64-bit editions) (2553313) Not applicable Not applicable CriticalRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Office 2010 Service Pack 2 (32-bit editions) (2598244) Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable 2589320 in MS11-089
Microsoft Office 2010 Service Pack 2 (64-bit editions) (2598244) Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable 2589320 in MS11-089
Microsoft Excel 2010 Service Pack 2 (32-bit editions) (3055044) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 3054981 in MS15-070
Microsoft Excel 2010 Service Pack 2 (64-bit editions) (3055044) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 3054981 in MS15-070
Microsoft PowerPoint 2010 Service Pack 2 (32-bit editions) (3055033) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 3054963 in MS15-070
Microsoft PowerPoint 2010 Service Pack 2 (64-bit editions) (3055033) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 3054963 in MS15-070
Microsoft Visio 2010 Service Pack 2 (32-bit editions) (3054876) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 2810068 in MS13-044
Microsoft Visio 2010 Service Pack 2 (64-bit editions) (3054876) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 2810068 in MS13-044
Microsoft Word 2010 Service Pack 2 (32-bit editions) (3055039) Not applicable ImportantInformation Disclosure Not applicable Not applicable ImportantRemote Code Execution ImportantRemote Code Execution Not applicable Not applicable 3054973 in MS15-070
Microsoft Word 2010 Service Pack 2 (64-bit editions) (3055039) Not applicable ImportantInformation Disclosure Not applicable Not applicable ImportantRemote Code Execution ImportantRemote Code Execution Not applicable Not applicable 3054973 in MS15-070
Microsoft Office 2013
Microsoft Office 2013 Service Pack 1 (32-bit editions) (3039734) ImportantRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Office 2013 Service Pack 1 (64-bit editions) (3039734) ImportantRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Office 2013 Service Pack 1 (32-bit editions) (3039798) Not applicable Not applicable CriticalRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Office 2013 Service Pack 1 (64-bit editions) (3039798) Not applicable Not applicable CriticalRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Office 2013 Service Pack 1 (32-bit editions) (3054816) Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable None
Microsoft Office 2013 Service Pack 1 (64-bit editions) (3054816) Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable None
Microsoft Excel 2013 Service Pack 1 (32-bit editions) (3054991) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 3054949 in MS15-070
Microsoft Excel 2013 Service Pack 1 (64-bit editions) (3054991) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 3054949 in MS15-070
Microsoft PowerPoint 2013 Service Pack 1 (32-bit editions) (3055029) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 3054999 in MS15-070
Microsoft PowerPoint 2013 Service Pack 1 (64-bit editions) (3055029) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 3054999 in MS15-070
Microsoft Visio 2013 Service Pack 1 (32-bit editions) (3054929) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Visio 2013 Service Pack 1 (64-bit editions) (3054929) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Word 2013 Service Pack 1 (32-bit editions) (3055030) Not applicable ImportantInformation Disclosure Not applicable Not applicable ImportantRemote Code Execution Not applicable Not applicable Not applicable 3054990 in MS15-070
Microsoft Word 2013 Service Pack 1 (64-bit editions) (3055030) Not applicable ImportantInformation Disclosure Not applicable Not applicable ImportantRemote Code Execution Not applicable Not applicable Not applicable 3054990 in MS15-070
Microsoft Office 2013 RT
Microsoft Office 2013 RT Service Pack 1 (3039798)[1] Not applicable Not applicable CriticalRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Office 2013 RT Service Pack 1 (3054816)[2] Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable None
Microsoft Excel 2013 RT Service Pack 1 (3054991)[2] Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable 3054949 in MS15-070
Microsoft PowerPoint 2013 RT Service Pack 1 (3055029)[2] Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Visio 2013 RT Service Pack 1 (64-bit editions) (3054929)[2] Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Word 2013 RT Service Pack 1 (3055030)[2] Not applicable ImportantInformation Disclosure Not applicable Not applicable ImportantRemote Code Execution Not applicable Not applicable Not applicable 3054990 in MS15-070
Microsoft Office 2016
Microsoft Office 2016 (32-bit editions) (3085538) Not applicable Not applicable CriticalRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Office 2016 (64-bit editions) (3085538) Not applicable Not applicable CriticalRemote Code Execution Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Visio 2016 (32-bit editions) (2920708) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Visio 2016 (64-bit editions) (2920708) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Word 2016 (32-bit editions) (2920691) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Word 2016 (64-bit editions) (2920691) Not applicable ImportantInformation Disclosure Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable None
Microsoft Office for Mac 2011
Microsoft Office for Mac 2011 (3081349) Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution ImportantRemote Code Execution ImportantRemote Code Execution ImportantRemote Code Execution 3073865 in MS15-070
Microsoft Office for Mac 2016
Microsoft Office for Mac 2016 (3082420) Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable Not applicable ImportantRemote Code Execution None
Other Office Software
Microsoft Office Compatibility Pack Service Pack 3 (2986254) Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable Not applicable Not applicable 2965210 in MS15-033
Microsoft Word Viewer (3055053) Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable Not applicable Not applicable 3054958 in MS15-070
Microsoft Word Viewer (3055054) Not applicable Not applicable Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution ImportantRemote Code Execution None

[1]As of September 2, 2015, this update is available via Windows Update.

[2]This update is available via Windows Update

*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).

Microsoft Office Services and Web Apps

Vulnerability Severity Rating and Maximum Security Impact by Affected Software
Affected Software Microsoft Office Memory Corruption Vulnerability - CVE-2015-1642 Unsafe Command Line Parameter Passing Vulnerability - CVE-2015-2423 Microsoft Office Remote Code Execution Vulnerability - CVE-2015-2466 Microsoft Office Memory Corruption Vulnerability - CVE-2015-2467 Microsoft Office Memory Corruption Vulnerability - CVE-2015-2468 Microsoft Office Memory Corruption Vulnerability - CVE-2015-2469 Microsoft Office Integer Underflow Vulnerability - CVE-2015-2470 Microsoft Office Memory Corruption Vulnerability - CVE-2015-2477 Updates Replaced
Microsoft SharePoint Server 2010
Word Automation Services on Microsoft SharePoint Server 2010 Service Pack 2 (3054960) Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable Not applicable Not applicable 3054833 in MS15-046
Microsoft SharePoint Server 2013
Word Automation Services on Microsoft SharePoint Server 2013 Service Pack 1 (3054858) Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable Not applicable Not applicable 3023055 in MS15-046
Microsoft Office Web Apps 2010
Microsoft Word Web Apps 2010 Service Pack 2 (3054974) Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable Not applicable Not applicable 3054843 in MS15-046
Microsoft Office Web Apps 2013
Microsoft Office Web Apps Server 2013 Service Pack 1 (3055003) Not applicable Not applicable Not applicable Not applicable ImportantRemote Code Execution Not applicable Not applicable Not applicable 3039748 in MS15-046

*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

CVE-2015-2423 discussed in this bulletin is also discussed in other bulletins being released in August. Do I need to install multiple updates to be protected from this vulnerability? 
Yes. To be protected from CVE-2015-2423, customers must apply all of the updates provided in this bulletin for their affected software, as well as the update for Internet Explorer provided in MS15-079. Likewise, customers running an affected version of Microsoft Windows must also install the applicable updates provided in MS15-088. Customers who do not install all of the updates available for their affected software will not be fully protected from the vulnerability.

MS15-080, MS15-081, and MS15-084 all address vulnerabilities in Microsoft Office. Are the security updates in the three bulletins related?
No. The security updates in MS15-080, MS15-081, and MS15-084 are not related. Customers should install the updates in both bulletins for the software installed on their systems.

Does this update contain any additional security-related changes to functionality? 
Yes. In addition to the changes that are listed for the vulnerabilities described in this bulletin, this update includes defense-in-depth updates to help make Microsoft Office more secure.

I have Microsoft Word 2010 installed. Why am I not being offered the 3055037 update? 
The 3055037 update only applies to systems running specific configurations of Microsoft Office 2010. Some configurations will not be offered the update.

There are multiple update packages available for some of the affected software. Do I need to install all the updates listed in the Affected Software table for the software?
Yes. Customers should apply all updates offered for the software installed on their systems.

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.

For example, 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 example, when an update applies to Microsoft Office 2013 products, only Microsoft Office 2013 may be specifically listed in the Affected Software table. However, the update could apply to Microsoft Word 2013, Microsoft Excel 2013, Microsoft Visio 2013, or any other Microsoft Office 2013 product that is not specifically listed in the Affected Software table.

Vulnerability Information

Multiple Microsoft Office Memory Corruption Vulnerabilities

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 vulnerability could use a specially crafted file to perform actions in the security context of the current user. The file could then, for example, take actions on behalf of the logged-on user with the same permissions as the current user. Exploitation of this vulnerability 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.

The security update addresses the vulnerabilities by correcting how Microsoft Office handles files in memory.

The following tables contain links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list:

Vulnerability title CVE number Publicly disclosed Exploited
Microsoft Office Memory Corruption Vulnerability CVE-2015-1642 No Yes
Microsoft Office Memory Corruption Vulnerability CVE-2015-2467 No No
Microsoft Office Memory Corruption Vulnerability CVE-2015-2468 No No
Microsoft Office Memory Corruption Vulnerability CVE-2015-2469 No No
Microsoft Office Memory Corruption Vulnerability CVE-2015-2477 No No

 

Mitigating Factors

Microsoft has not identified any mitigating factors for these vulnerabilities.

Workarounds

Microsoft has not identified any workarounds for these vulnerabilities. 

Unsafe Command Line Parameter Passing Vulnerability - CVE-2015-2423

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. The update addresses the vulnerability by improving how Notepad and Microsoft Office programs are executed from Internet Explorer.

Important To be protected from this vulnerability, customers must apply the updates provided in this bulletin, as well as the update for Internet Explorer provided in MS15-079. Likewise, customers running an affected version of Microsoft Windows must also install the applicable updates provided in MS15-088.

This vulnerability has been publicly disclosed. It has been assigned Common Vulnerability and Exposure number CVE-2015-2423. When this bulletin was originally released, Microsoft had not received any information to indicate that this issue had been publicly used to attack customers.

Mitigating Factors

Microsoft has not identified any mitigating factors for this vulnerability.

Workarounds

The following workaround may be helpful in your situation:

  • Remove the IE elevation policies for Word, Excel, PowerPoint, and Visio

    Warning If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

    1. Click Start, click Run, type Regedit in the Open box, and then click OK.

    2. Navigate to the following registry location:

      HKEY_LOCAL_MACHINE\Software\Microsoft\Internet Explorer\Low Rights\ElevationPolicy
      
    3. For each of the following subkeys, perform the steps that follow:

      {000209FF-0000-0000-C000-000000000046}

      {2BBE903C-2776-4574-9855-EC1597ABE3D6}

      {63F463ED-322A-4DE8-8E6F-65DD293F7461}

      {FC88B53C-9B2A-1A25-5867-C8612E79DBF6}

      1. Select the subkey.

      2. Click the File menu and then click Export.

      3. In the Export Registry File dialog box, type <a unique file name> and then click Save.

        Note This will create a backup of this registry key in the My Documents folder by default.

      4. Click the File menu and then select Delete.

      5. Click Yes.

      6. Log all users off and on again, or then restart the computer.

    How to undo the workaround

    1. Click Start, click Run, type Regedit in the Open box, and then click OK.

    2. Navigate to the following registry location:

      HKEY_LOCAL_MACHINE\Software\Microsoft\Internet Explorer\Low Rights\ElevationPolicy
      
    3. For each of the four .reg files, perform the following steps:

      1. Click the File menu and then select Import.
      2. In the Import Registry File dialog box, select the appropriate file and then click Open.
      3. Exit the Registry Editor.
      4. Restart the computer.

Microsoft Office Remote Code Execution Vulnerability - CVE-2015-2466

A remote code execution vulnerability exists in Microsoft Office software when the Office software fails to properly validate templates. An attacker who successfully exploited this vulnerability could run arbitrary code in the context of the current user. Exploitation of this vulnerability requires that a user open a specially crafted template file with an affected version of Microsoft Office software.

An attacker who successfully exploited this vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker could take complete 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.

In an email attack scenario an attacker could exploit the vulnerability 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 file share (or leverage a compromised website that accepts or hosts user-provided content) that contains a specially crafted file that is designed to exploit the vulnerability. An attacker would have no way to force users to visit the website or file share. 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.

Alternatively, an attacker could launch a “Man-in-the-middle” attack (intercept the traffic between source and destination) and modify the template contents to include malicious code.

The security update addresses the vulnerability by correcting how Office validates office templates prior to use.

Microsoft received information about the vulnerability through coordinated vulnerability disclosure. When this security bulletin was issued, Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers.

Mitigating Factors

Microsoft has not identified any mitigating factors for this vulnerability.

Workarounds

Microsoft has not identified any workarounds for this vulnerability.

Microsoft Office Integer Underflow Vulnerability - CVE-2015-2470

A remote code execution vulnerability exists when Office decreases an integer value beyond its intended minimum value. Exploitation of this vulnerability requires that a user open a specially crafted Office file with an affected version of Microsoft Office software.

An attacker who successfully exploited this vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker could take complete 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.

In an email attack scenario an attacker could exploit the vulnerability 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 vulnerability. 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.

The security update addresses the vulnerability by correcting how Office handles integer bounds checking.

Microsoft received information about the vulnerability through coordinated vulnerability disclosure. When this security bulletin was issued, Microsoft had not received any information to indicate that this vulnerability had been publicly used to attack customers.

Mitigating Factors

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 (August 11, 2015): Bulletin published.
  • V2.0 (September 2, 2015): Bulletin revised to announce that the 3039798 update for Microsoft Office 2013 RT Service Pack 1 is available via Windows Update.
  • V3.0 (October 13, 2015): Revised bulletin to announce the availability of update packages for Microsoft Office 2016, Microsoft Visio 2016, and Microsoft Word 2016. Customers running Microsoft Office 2016, Microsoft Visio 2016, or Microsoft Word 2016 should apply the applicable updates to be protected from the vulnerabilities discussed in this bulletin. The majority of customers have automatic updating enabled and will not need to take any action because the updates will be downloaded and installed automatically.

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