Multiple Microsoft Browser Memory Corruption Vulnerabilities
Multiple remote code execution vulnerabilities exist in the way that Microsoft browsers access objects in memory.

The vulnerabilities could corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user.

An attacker who successfully exploited the vulnerabilities could gain the same user rights as the current user.
If the current user is logged on with administrative user rights, the attacker 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.
An attacker could host a specially crafted website that is designed to exploit the vulnerabilities through Microsoft browsers, and then convince a user to view the website.

The attacker could also take advantage of compromised websites, or websites that accept or host user-provided content or advertisements, by adding specially crafted content that could exploit the vulnerabilities.
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 via an enticement in email or instant message, or by getting them to open an email attachment.
The update addresses the vulnerabilities by modifying how Microsoft browsers handle 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 Browser Memory Corruption Vulnerability

CVE-2016-7195

No

No

Microsoft Browser Memory Corruption Vulnerability

CVE-2016-7196

No

No

Microsoft Browser Memory Corruption Vulnerability

CVE-2016-7198

No

No

Microsoft Browser Memory Corruption Vulnerability

CVE-2016-7241

No

No

Mitigating Factors
Microsoft has not identified any mitigating factors for these vulnerabilities.

Workarounds
Microsoft has not identified any workarounds for these vulnerabilities.

FAQ
I am running Internet Explorer on Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, or Windows Server 2012 R2.

Does this mitigate these vulnerabilities? Yes.

By default, Internet Explorer on Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, and Windows Server 2012 R2 runs in a restricted mode that is known as Enhanced Security Configuration.

Enhanced Security Configuration is a group of preconfigured settings in Internet Explorer that can reduce the likelihood of a user or administrator downloading and running specially crafted web content on a server.

This is a mitigating factor for websites that you have not added to the Internet Explorer Trusted sites zone.
Can EMET help mitigate attacks that attempt to exploit these vulnerabilities? Yes.

The Enhanced Mitigation Experience Toolkit (EMET) enables users to manage security mitigation technologies that help make it more difficult for attackers to exploit memory corruption vulnerabilities in a given piece of software.

EMET can help mitigate attacks that attempt to exploit these vulnerabilities in Internet Explorer on systems where EMET is installed and configured to work with Internet Explorer.
For more information about EMET, see the Enhanced Mitigation Experience Toolkit.

Microsoft Browser Information Disclosure Vulnerability CVE-2016-7199
An information disclosure vulnerability exists when affected Microsoft browsers improperly allow cross-frame interaction.

An attacker who successfully exploited this vulnerability could obtain the browser frame or window state from a different domain.
For an attack to be successful, an attacker must persuade a user to open a malicious website from a secure website.

This update addresses the vulnerability by denying permission to read state of the object model, to which frames or windows in a different domain shouldn’t have access to.
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 Browser Information Disclosure Vulnerability

CVE-2016-7199

Yes

No

Mitigating Factors
Microsoft has not identified any mitigating factors for this vulnerability.

Workarounds
Microsoft has not identified any workarounds for this vulnerability.

Microsoft Browser Information Disclosure Vulnerability CVE-2016-7227
An information disclosure vulnerability exists when affected Microsoft scripting engines do not properly handle objects in memory.

The vulnerability could allow an attacker to detect specific files on the user’s computer.
In a web-based attack scenario, an attacker could host a website that is used to attempt to exploit the vulnerability.
In addition, compromised websites and websites that accept or host user-generated content could contain specially crafted content that could exploit the vulnerability.
In all cases, however, an attacker would have no way to force a user to view the attacker-controlled content.
Instead, an attacker would have to convince users to take action.

For example, an attacker could trick users into clicking a link that takes them to the attacker’s site.
An attacker who successfully exploited the vulnerability could potentially read data that was not intended to be disclosed. Note that the vulnerability would not allow an attacker to execute code or to elevate a user’s rights directly, but the vulnerability could be used to obtain information in an attempt to further compromise the affected system.

The update addresses the vulnerability by helping to restrict what information is returned to Internet Explorer.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 Browser Information Disclosure Vulnerability

CVE-2016-7227

No

No

Mitigating Factors
Microsoft has not identified any mitigating factors for this vulnerability.

Workarounds
Microsoft has not identified any workarounds for this vulnerability.

Microsoft Browser Information Disclosure Vulnerability CVE-2016-7239
An information disclosure vulnerability exists when the Microsoft browser XSS filter is abused to leak sensitive page information.

An attacker who successfully exploited the vulnerability could obtain sensitive information from certain web pages.
To exploit the vulnerability, an attacker would have to log on to an affected system and run a specially crafted application.

The update addresses the vulnerability by changing how the XSS filter handles RegEx.
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 Browser Information Disclosure Vulnerability

CVE-2016-7239

No

No

Mitigating Factors
Microsoft has not identified any mitigating factors for this vulnerability.

Workarounds
Microsoft has not identified any workarounds for this vulnerability.

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