Windows 10 emergency update KB4078130 releases

Microsoft has just made available update KB4078130 for Windows 10 to disable the microcode update from Intel that was meant to fix the Spectre (variant 2) processor vulnerability.

Recently Intel started rolling out a microcode update to address the Spectre vulnerability, but as it turns out the update had its own problems that can result in sudden reboots and number of unpredictable behaviors, including data loss or corruption.

On January 22, Intel began recommending customers to stop installing the update on impacted processors until the update is fix. Consequently, Microsoft is now pushing update KB4078130 to disable the Intel microcode mitigation to prevent devices from unwanted behaviors.

KB4078130 is available for all versions of Windows 10 as well as for Windows 7 and Windows 8.1, and Microsoft is recommending to manually download and install the update on affected devices to disable the mitigation known as CVE-2017-5715 – “Branch target injection vulnerability.”

The update isn’t available through Windows Update, which means that you must download the patch from the Microsoft Update Catalog, and double-click the file to install it.

How to manually disable Intel’s Spectre mitigation

Alternatively, Microsoft is also offering the instructions to manually disable and enable the Spectre mitigation making changes to the registry.

Warning: It’s very important to note that modifying the Windows Registry can cause serious problems if not used properly. It’s assumed that you know what you’re doing and you have created a full backup of your system before proceeding.
  1. Open Start.

  2. Search for Command Prompt, right-click the top result and select Run as administrator.

  3. Type the following commands to disable the disable variant 2: CVE 2017-5715″Branch Target Injection and press Enter on each line:

    reg add "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /v FeatureSettingsOverride /t REG_DWORD /d 1 /f
    reg add "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /v FeatureSettingsOverrideMask /t REG_DWORD /d 1 /f

Once you’ve completed the steps, restart your computer to apply the changes.

If you must enable the update again, use these steps:

  1. Open Start.

  2. Search for Command Prompt, right-click the top result and select Run as administrator.

  3. Type the following commands to disable the variant 2: CVE 2017-5715″Branch Target Injection and press Enter on each line:

    reg add "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /v FeatureSettingsOverride /t REG_DWORD /d 0 /f
    reg add "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management" /v FeatureSettingsOverrideMask /t REG_DWORD /d 1 /f

After completing the steps, restart your device to apply the changes.

According to the software giant, there are yet no reports that the Spectre vulnerability has been used to attack customers in any way. However, the company also recommends to re-enable the mitigation once Intel fixes its issues.