Like the update for Windows 10 Version 1709 and 1703, Microsoft has released the cumulative updates for Windows 10 Version 1607. This is an important update which fixes some security vulnerabilities and some other fixes to problems faced by users.
The Microsoft knowledgebase article only lists down one update which is included in KB4056890.
Security updates to Internet Explorer, Microsoft Scripting Engine, Microsoft Edge, Windows Graphics, Windows Kernel, Windows Subsystem for Linux, and the Windows SMB Server.
But there are several known issues which have not been fixed yet. If you are using a third-party antivirus, you may need to check if your antivirus has updated the ALLOW REGKEY registry value. Otherwise, the user will also need to update their Antivirus products before installing this update.
KB4056890 direct download links
If you have already enabled Windows Update, you will get this update through Windows Update. But if you want to download and install it manually as in case you want to install it on multiple system without using Internet bandwidth, you may download the MSU file from the links below and just run it on the system where you want it installed. Just make sure Windows version should be 1607.