Improvements and fixes
This security update includes quality improvements. No new operating system features are being introduced in this update. Key changes include:
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 affects PowerShell remoting loop back using non-administrator accounts. For more details, see Windows Security change affecting PowerShell.
Addresses an issue related to the date format for the Japanese Era calendar. For more information, see KB4469068.
Addresses an issue that causes the GetCalendarInfo function to return a wrong value for the Japanese Era. For more information, see KB4469068.
Security updates to Windows Kernel, Windows Storage and Filesystems, Windows Wireless Networking, and the Microsoft JET Database Engine.
For more information about the resolved security vulnerabilities, please refer to the Security Update Guide.
Known issues in this update
Some users are reporting activation failures and "Not genuine" notifications starting around January 8, 2019, or later, on volume-licensed Windows 7 KMS clients. Notifications may state:
Note The timing of this issue coincides with the release of the January updates (KB4480960 and KB4480970) that were released on Tuesday, January 8, 2019. These events are not related.
The issue has been corrected on the backend Microsoft Activation and Validation servers. If you are affected by this issue, please follow the guidance in the Knowledge Base Help article, KB4487266.
Local users who are part of the local “Administrators“ group may not be able to remotely access shares on Windows Server 2008 R2 and Windows 7 machines after installing the January 8th, 2019 security updates. This does not affect domain accounts in the local "Administrators" group.
This issue is resolved in KB4487345.
Applications that use a Microsoft Jet database with the Microsoft Access 97 file format may fail to open if the database has column names greater than 32 characters. The database will fail to open with the error, “Unrecognized Database Format”.
This issue is resolved in KB4486564.
After installing this update, virtual machines (VM) may fail to restore successfully if the VM has been saved and restored once before. The error message is, “Failed to restore the virtual machine state: Cannot restore this virtual machine because the saved state data cannot be read. Delete the saved state data and then try to start the virtual machine. (0xC0370027).”
This affects AMD Bulldozer Family 15h, AMD Jaguar Family 16h, and AMD Puma Family 16h (second generation) microarchitectures.
This issue is resolved in KB4490511.
After installing this update, Internet Explorer 11 and other applications that use WININET.DLL may have authentication issues. This occurs when two or more people use the same user account for multiple, concurrent login sessions on the same Windows Server machine, including Remote Desktop Protocol (RDP) and Terminal Server logons. Symptoms reported by customers include, but may not be limited to:
Issues when downloading files.
This issue is resolved in KB4493448.
How to get this update
Before installing this update
Microsoft strongly recommends you install the latest servicing stack update (SSU) for your operating system before installing the latest Rollup. SSUs improve the reliability of the update process to mitigate potential issues while installing the Rollup and applying Microsoft security fixes.
Install this update
This update is now available for installation through WSUS. To get the stand-alone package for this update, go to the Microsoft Update Catalog website.
For a list of the files that are provided in this update, download the file information for update 4480960.