Microsoft released an urgent security update today for Internet Explorer on all currently supported versions of Windows. Here is the new security update. Microsoft Security Bulletin MS15-078 - Critical Vulnerability in Microsoft Font Driver Could Allow Remote Code Execution (3079904) Published. Microsoft today released one of its rare 'out-of-band' security updates to patch a vulnerability in all versions of its Windows Server software.
Microsoft issues emergency patch for all versions of Windows. This is the second 'critical' out-of-band patch issued in as many months.
Microsoft Security Bulletin MS1. Critical. A remote code execution vulnerability exists when Internet Explorer improperly accesses objects in memory.
This security update addresses the vulnerability first described in Microsoft Security Advisory 2963983. Recommendation. Microsoft has just announced a brand new security update for all Windows versions currently on the market, obviously excepting Windows XP, whose support ended earlier. Microsoft today deviated from its regular pattern of releasing security updates on the second Tuesday of each month, pushing out an emergency patch to plug.
This vulnerability could corrupt memory in such a way that an attacker could execute arbitrary code in the context of the current user. To view this vulnerability as a standard entry in the Common Vulnerabilities and Exposures list, click the link in the following table: Vulnerability title. CVE number. Internet Explorer Memory Corruption Vulnerability. CVE- 2. 01. 4- 1.
Mitigating Factors. Mitigation refers to a setting, common configuration, or general best- practice, existing in a default state, that could reduce the severity of exploitation of a vulnerability. The following mitigating factors may be helpful in your situation: In a web- based attack scenario, an attacker could host a specially crafted website that is designed to exploit this vulnerability through Internet Explorer, 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.
These websites could contain specially crafted content that could exploit this 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 getting them to click a link in an email message or in an Instant Messenger message that takes users to the attacker's website, or by getting them to open an attachment sent through email. An attacker who successfully exploited this vulnerability could gain the same user rights as the current user.
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. By default, the modern, immersive browsing experience on Windows 8 and Windows 8. Enhanced Protected Mode (EPM).
For example, customers using the touch- friendly Internet Explorer 1. Windows tablets are using Enhanced Protected Mode by default. Enhanced Protected Mode uses advanced security protections that can help mitigate against exploitation of this vulnerability on 6. See the FAQ section for this vulnerability for more information about Enhanced Protected Mode.
By default, all supported versions of Microsoft Outlook, Microsoft Outlook Express, and Windows Mail open HTML email messages in the Restricted sites zone. The Restricted sites zone, which disables script and Active. X controls, helps reduce the risk of an attacker being able to use this vulnerability to execute malicious code. If a user clicks a link in an email message, the user could still be vulnerable to exploitation of this vulnerability through the web- based attack scenario. By default, Internet Explorer on Windows Server 2. Windows Server 2.
Windows Server 2. R2, Windows Server 2. Windows Server 2. R2 runs in a restricted mode that is known as Enhanced Security Configuration. This mode mitigates this vulnerability.
See the FAQ section for this vulnerability for more information about Internet Explorer Enhanced Security Configuration. Workarounds. Workaround refers to a setting or configuration change that does not correct the underlying vulnerability but would help block known attack vectors before you apply the update.
Microsoft has tested the following workarounds and states in the discussion whether a workaround reduces functionality: Unregister VGX. DLL For 3. 2- bit Windows systems. Note. В The following command must be entered from an elevated command prompt. From an elevated command prompt, enter the following command. System. Root%\System.
Common. Program. Files%\Microsoft Shared\VGX\vgx. A dialog box should appear after the command is run to confirm that the un- registration process has succeeded. Click OK to close the dialog box. Note that the - s command line switch can be used to suppress the dialog box in order to allow this command to be scripted. Close and reopen Internet Explorer for the changes to take effect. For 6. 4- bit Windows systems.
Note. В For users running 6. VGX. DLL workaround documented in version 1. Microsoft Security Advisory 2.
Note. В The following commands must be entered from an elevated command prompt. From an elevated command prompt, enter the following commands. System. Root%\System. Common. Program. Files%\Microsoft Shared\VGX\vgx.
System. Root%\System. Common. Program. Files(x. Microsoft Shared\VGX\vgx. A dialog box should appear after each command is run to confirm that the un- registration process has succeeded. Click OK to close the dialog box. Note that the - s command line switch can be used to suppress the dialog box in order to allow these commands to be scripted. Close and reopen Internet Explorer for the changes to take effect.
Impact of Workaround. В Applications that render VML will no longer do so once vgx. Also note that software that redistributes vgx. This workaround may need to be reverted before the software can be installed. How to undo this workaround. The security update does not re- register vgx. To re- register vgx.
Note. В The following commands must be entered from an elevated command prompt. For 3. 2- bit Windows systems, from an elevated command prompt, enter the following command. System. Root%\System. Common. Program. Files%\Microsoft Shared\VGX\vgx. A dialog box should appear after the command is run to confirm that the re- registration process has succeeded.
Click OK to close the dialog box. Close and reopen Internet Explorer for the changes to take effect. Note that the - s command line switch can be used to suppress the dialog box in order to allow this command to be scripted. For 6. 4- bit Windows systems, from an elevated command prompt, enter the following commands. System. Root%\System. Common. Program. Files%\Microsoft Shared\VGX\vgx.
System. Root%\System. Common. Program. Files(x. Microsoft Shared\VGX\vgx. A dialog box should appear after each command is run to confirm that the re- registration process has succeeded. Click OK to close the dialog box. Close and reopen Internet Explorer for the changes to take effect. Note that the - s command line switch can be used to suppress the dialog box in order to allow these commands to be scripted.
В Set Internet and Local intranet security zone settings to "High" to block Active. X Controls and Active Scripting in these zones. You can help protect against exploitation of this vulnerability by changing your settings for the Internet security zone to block Active.
X controls and Active Scripting. You can do this by setting your browser security to High. To raise the browsing security level in Internet Explorer, perform the following steps: On the Internet Explorer Tools menu, click Internet Options. In the Internet Options dialog box, click the Security tab, and then click Internet.
Under Security level for this zone, move the slider to High. This sets the security level for all websites you visit to High. Click Local intranet. Under Security level for this zone, move the slider to High.
This sets the security level for all websites you visit to High. Click OK to accept the changes and return to Internet Explorer.
Note If no slider is visible, click Default Level, and then move the slider to High. Note Setting the level to High may cause some websites to work incorrectly. If you have difficulty using a website after you change this setting, and you are sure the site is safe to use, you can add that site to your list of trusted sites.
This will allow the site to work correctly even with the security setting set to High. Impact of workaround. There are side effects to blocking Active. X Controls and Active Scripting. Many websites that are on the Internet or on an intranet use Active. X or Active Scripting to provide additional functionality. For example, an online e- commerce site or banking site may use Active.
X Controls to provide menus, ordering forms, or even account statements. Blocking Active. X Controls or Active Scripting is a global setting that affects all Internet and intranet sites. If you do not want to block Active. X Controls or Active Scripting for such sites, use the steps outlined in "Add sites that you trust to the Internet Explorer Trusted sites zone". Add sites that you trust to the Internet Explorer Trusted sites zone.
After you set Internet Explorer to block Active. X controls and Active Scripting in the Internet zone and in the Local intranet zone, you can add sites that you trust to the Internet Explorer Trusted sites zone. This will allow you to continue to use trusted websites exactly as you do today, while helping to protect yourself from this attack on untrusted sites. We recommend that you add only sites that you trust to the Trusted sites zone. To do this, perform the following steps: In Internet Explorer, click Tools, click Internet Options, and then click the Security tab.
In the Select a web content zone to specify its current security settings box, click Trusted Sites, and then click Sites. If you want to add sites that do not require an encrypted channel, click to clear the Require server verification (https: ) for all sites in this zone check box. In the Add this website to the zone box, type the URL of a site that you trust, and then click Add.
Repeat these steps for each site that you want to add to the zone. Click OK two times to accept the changes and return to Internet Explorer. Note Add any sites that you trust not to take malicious action on your system.
Two in particular that you may want to add are *. These are the sites that will host the update, and it requires an Active. X Control to install the update. В Configure Internet Explorer to prompt before running Active Scripting or to disable Active Scripting in the Internet and Local intranet security zone. You can help protect against exploitation of this vulnerability by changing your settings to prompt before running Active Scripting or to disable Active Scripting in the Internet and Local intranet security zone.