==================================================================== CERT-Renater Note d'Information No. 2017/VULN068 _____________________________________________________________________ DATE : 15/03/2017 HARDWARE PLATFORM(S): / OPERATING SYSTEM(S): Systems running Microsoft Office versions 2007, 2010, 2013, 2013 RT, 2016, for Mac 2011, 2016 for Mac, SharePoint Server versions 2007, 2010, 2013, Office Web Apps versions 2010, 2013, Lync for Mac. ===================================================================== KB4013241 https://technet.microsoft.com/en-us/library/security/MS17-014 ____________________________________________________________________ Microsoft Security Bulletin MS17-014: , Security Update for Microsoft Office (4013241) Bulletin Number: MS17-014 Bulletin Title: Security Update for Microsoft Office Severity: Important KB Article: 4013241 Version: 1.0 Published Date: 14/03/2017 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 about the vulnerabilities, see the Affected Software and Vulnerability Severity Ratings section. The security update addresses the vulnerabilities by correcting how: - -Correcting how Office handles objects in memory - -Changing the way certain functions handle objects in memory - -Properly initializing the affected variable - -Helping to ensure that SharePoint Server properly sanitizes web requests - -Correcting how the Lync for Mac 2011 client validates certificates For more information about the vulnerabilities, see the Vulnerability Information section. For more information about this update, see Microsoft Knowledge Base Article 4013241. Affected Software Microsoft Office 2007 Microsoft Office 2010 Microsoft Office 2013 Microsoft Office 2013 RT Microsoft Office 2016 Microsoft Office for Mac 2011 Microsoft Office 2016 for Mac Microsoft SharePoint Server 2007 Microsoft SharePoint Server 2010 Microsoft SharePoint Server 2013 Microsoft Office Web Apps 2010 Microsoft Office Web Apps 2013 Microsoft SharePoint Server 2013 Microsoft Lync for Mac Update FAQ Do these updates contain any additional security-related changes? 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 improve security-related features. I have Microsoft Word 2010 installed. Why am I not being offered the 3178686 update? The 3178686 update only applies to systems running specific configurations of Microsoft Office 2010. Some configurations will not be offered the update. 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 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 the Preview Pane is not an attack vector for these vulnerabilities. The security update addresses the vulnerabilities by correcting how Office handles objects in memory. Mitigating Factors Microsoft has not identified any mitigating factors for these vulnerabilities. Workarounds The following workaround may be helpful in your situation: Workaround for CVE-2017-0019 Use Microsoft Office File Block policy to prevent Office from opening RTF documents from unknown or untrusted sources 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. For Office 2016 a. Run regedit.exe as Administrator and navigate to the following subkey: [HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Word\Security\FileBlock] b. Set the RtfFiles DWORD value to 2. c. Set the OpenInProtectedView DWORD value to 0. Impact of Workaround. Users who have configured the File Block policy and have not configured a special exempt directory as discussed in Microsoft Knowledge Base Article 922849 will be unable to open documents saved in the RTF format. How to undo the workaround For Office 2016 a. Run regedit.exe as Administrator and navigate to the following subkey: [HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Word\Security\FileBlock] d. Set the RtfFiles DWORD value to 0. e. Set the OpenInProtectedView DWORD value to 0. Microsoft Office Information Disclosure Vulnerability CVE-2017-0027 An information disclosure vulnerability exists when Microsoft Office improperly discloses the contents of its memory. An attacker who exploited the vulnerability could use the information to compromise the users computer or data. To exploit the vulnerability, an attacker could craft a special document file and then convince the user to open it. An attacker must know the memory address location where the object was created. The update addresses the vulnerability by changing the way certain functions handle objects in memory. Mitigating Factors Microsoft has not identified any mitigating factors for this vulnerability. Workarounds Microsoft has not identified any workarounds for this vulnerability. Microsoft Office Denial of Service Vulnerability CVE-2017-0029 A denial of service vulnerability exists when a specially crafted file is opened in Microsoft Office. An attacker who successfully exploited the vulnerability could cause Office to stop responding. Note that the denial of service would not allow an attacker to execute code or to elevate the attacker's user rights. For an attack to be successful, this vulnerability requires that a user open a specially crafted file with an affected version of Microsoft Office. In an email attack scenario, an attacker could exploit the vulnerability by sending a specially crafted file to the user and by convincing the user to open the file. The security update addresses the vulnerability by correcting how Microsoft Office handles objects in memory. Mitigating Factors Microsoft has not identified any mitigating factors for this vulnerability. Workarounds Microsoft has not identified any workarounds for this vulnerability. Microsoft Office Information Disclosure Vulnerability CVE-2017-0105 An information disclosure vulnerability exists when Microsoft Office software reads out of bound memory due to an uninitialized variable, which could disclose the contents of memory. An attacker who successfully exploited the vulnerability could view out of bound memory. Exploitation of the vulnerability requires that a user open a specially crafted file with an affected version of Microsoft Office software. The security update addresses the vulnerability by properly initializing the affected variable. Mitigating Factors Microsoft has not identified any mitigating factors for this vulnerability. Workarounds Microsoft has not identified any workarounds for this vulnerability. Microsoft SharePoint XSS Vulnerability CVE-2017-0107 An elevation of privilege vulnerability exists when Microsoft SharePoint Server does not properly sanitize a specially crafted web request to an affected SharePoint server. An authenticated attacker could exploit the vulnerability by sending a specially crafted request to an affected SharePoint server. An attacker who successfully exploited the vulnerability could then perform cross-site scripting attacks on affected systems and run script in the security context of the current user. These attacks could allow the attacker to read content that the attacker is not authorized to read, use the victim's identity to take actions on the SharePoint site on behalf of the victim, such as change permissions and delete content, and to inject malicious content in the browser of the victim. The security update addresses the vulnerability by helping to ensure that SharePoint Server properly sanitizes web requests. Mitigating Factors Microsoft has not identified any mitigating factors for this vulnerability. Workarounds Microsoft has not identified any workarounds for this vulnerability. Microsoft Lync for Mac Certificate Validation Vulnerability CVE-2017-0129 A security feature bypass exists when the Lync for Mac 2011 client fails to properly validate certificates. An attacker who successfully exploited this vulnerability could tamper with trusted communications between the server and target client. To exploit the vulnerability an attacker would need to intercept and tamper with network traffic. The security update addresses the vulnerability by correcting how the Lync for Mac 2011 client validates certificates. 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 here 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. 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