In addition to today's patch for the small number of users running the October 2018 Update, Microsoft has also released a patch for the April 2018 Update which brings the build version to 17134.407. The patch includes additional Spectre vulnerability protections for users running AMD CPUs, plus a fix that prevented Microsoft Edge users from accessing the F12 developer tools. Lastly, this build brings the usual security updates for Microsoft Edge, the Windows kernel and more, and you can learn more in the full release notes below:
- Provides protections against an additional subclass of speculative execution side-channel vulnerability known as Speculative Store Bypass (CVE-2018-3639) for AMD-based computers. 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 these guidance documents to enable mitigations for Speculative Store Bypass (CVE-2018-3639). Additionally, use the mitigations that have already been released for Spectre Variant 2 (CVE-2017-5715) and Meltdown (CVE-2017-5754).
- Addresses an issue that may prevent developer tools (F12) from starting in Microsoft Edge.
- Security updates to Microsoft Edge, Internet Explorer, Windows Scripting, Windows App Platform and Frameworks, Windows Graphics, Windows Graphics, Windows Media, Windows Wireless Networking, Windows Kernel, and Windows Server .
If you haven't done so, you can download the update by opening the Settings app, going to Updates & Security, and then hitting the Check for updates button. However, there's a chance that doing that may get you the October 2018 update instead: Microsoft has finally re-released the major update today and you can get it via Windows Update, though the company said that it is "slowly throttling up this availability while we carefully monitor data and feedback."