Microsoft Security Bulletin MS16-002 - Critical
Cumulative Security Update for Microsoft Edge (3124904)
Published: January 12, 2016
This security update resolves vulnerabilities in Microsoft Edge. The vulnerabilities could allow remote code execution if a user views a specially crafted webpage using Microsoft Edge. An attacker who successfully exploited the vulnerabilities could gain the same user rights as 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.
This security update is rated Critical for Microsoft Edge on Windows 10. For more information, see the Affected Software section.
The update addresses the vulnerability by modifying how Microsoft Edge handles objects in memory.
For more information about the vulnerability, see the Vulnerability Information section.
For more information about this update, see Microsoft Knowledge Base Article 3124904.
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.
|**Operating System**||**Component**||**Maximum Security Impact**||**Aggregate Severity Rating**||**Updates Replaced**|
|[Windows 10 for 32-bit Systems](https://support.microsoft.com/kb/3124266) (3124266)||Microsoft Edge||Remote Code Execution||Critical||(https://support.microsoft.com/kb/3116869) in MS15-125|
|[Windows 10 for x64-based Systems](https://support.microsoft.com/kb/3124266) (3124266)||Microsoft Edge||Remote Code Execution||Critical||(https://support.microsoft.com/kb/3116869) in MS15-125|
|[Windows 10 Version 1511 for 32-bit Systems](https://support.microsoft.com/kb/3124263) (3124263)||Microsoft Edge||Remote Code Execution||Critical||(https://support.microsoft.com/kb/3116900) in MS15-125|
|[Windows 10 Version 1511 for x64-based Systems](https://support.microsoft.com/kb/3124263) (3124263)||Microsoft Edge||Remote Code Execution||Critical||(https://support.microsoft.com/kb/3116900) in MS15-125|
Customers running Windows 10 or Windows 10 Version 1511 who have Citrix XenDesktop installed will not be offered the update. Because of a Citrix issue with the XenDesktop software, users who install the update will be prevented from logging on. To stay protected, Microsoft recommends uninstalling the incompatible software and installing this update. Customers should contact Citrix for more information and help with this XenDesktop software issue.
The third-party products that this bulletin discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.
Note Windows Server Technical Preview 3 and Windows Server Technical Preview 4 are affected. Customers running these operating systems are encouraged to apply the update, which is available via Windows Update.
Does this update contain any additional security-related changes to functionality?
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.
Severity Ratings and Vulnerability Identifiers
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 January bulletin summary.
Where specified in the Severity Ratings and Impact table, Critical, Important, and Moderate values indicate severity ratings. For more information, see Security Bulletin Severity Rating System. Refer to the following key for the abbreviations used in the table to indicate maximum impact:
|RCE||Remote Code Execution|
|EoP||Elevation of Privilege|
|SFB||Security Feature Bypass|
|**Vulnerability Severity Ratings and Impact**|
|**CVE number**||**Vulnerability Title**||**Microsoft Edge**|
|[CVE-2016-0003](http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=cve-2016-0003)||Microsoft Edge Memory Corruption Vulnerability||
(Windows 10 Version 1511 is not affected)
**Critical / RCE** Windows Servers: **Moderate / RCE**
|[CVE-2016-0024](http://www.cve.mitre.org/cgi-bin/cvename.cgi?name=cve-2016-0024)||Scripting Engine Memory Corruption Vulnerability||Windows Clients **Critical / RCE** Windows Servers: **Moderate / RCE**|
Microsoft Edge Memory Corruption Vulnerability – CVE-2016-0003
A remote code execution vulnerability exists when Microsoft Edge improperly accesses objects in memory. The vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user.
An attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft Edge, and then convince a user to view the website. The attacker could also take advantage of compromised websites and websites that accept or host user-provided content or advertisements by adding specially crafted content that could exploit the vulnerability. In all cases, however, an attacker would have no way to force users to view the attacker-controlled content. Instead, an attacker would have to convince users to take action, typically by way of enticement in an email or Instant Messenger message, or by getting them to open an attachment sent through email.
An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, an attacker who successfully exploited the vulnerability could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. The update addresses the vulnerability by modifying how Microsoft Edge handles objects in memory.
The following table contains links to the standard entry for each vulnerability in the Common Vulnerabilities and Exposures list:
|Vulnerability title||CVE number||Publicly disclosed||Exploited|
|Microsoft Edge Memory Corruption Vulnerability||CVE-2016-0003||No||No|
|Vulnerability title||CVE number||Publicly disclosed||Exploited|
|Scripting Engine Memory Corruption Vulnerability||CVE-2016-0024||No||No|