KB4284819

Provides protections from an additional subclass of speculative execution side channel vulnerability known as Speculative Store Bypass (CVE-2018-3639). These protections aren't enabled by default. For Windows client (IT pro) guidance, follow the instructions in KB4073119. For Windows Server guidance, follow the instructions in KB4072698. Use this guidance document to enable mitigations for Speculative Store Bypass (CVE-2018-3639) in addition to the mitigations that have already been released for Spectre Variant 2 (CVE-2017-5715) and Meltdown (CVE-2017-5754).

Addresses an issue in Microsoft Edge that causes incorrect responses to XML requests.

Adds support for the SameSite cookie web standard to Microsoft Edge and Internet Explorer.

Addresses an issue with Internet Explorer that prevents it from using an updated version of location services.

Addresses an issue where firmware updates cause devices to go into BitLocker recovery mode when BitLocker is enabled, but Secure Boot is disabled or not present. This update prevents firmware installation on devices in this state. Administrators can install firmware updates by:

1. Temporarily suspending BitLocker.

2. Immediately installing firmware updates before the next OS startup.

3. Immediately restarting the device so that BitLocker doesn’t remain in the suspended state.

Addresses a binary serialization compatibility issue for the CultureAwareComparer class.

Security updates to Internet Explorer, Microsoft Edge, Microsoft scripting engine, Windows Desktop Bridge, Windows apps, Windows shell, Windows storage and filesystems, Windows app platform and frameworks, Windows virtualization and kernel, Windows wireless networking, and Windows Server.