Windows 10: Disable updates from non Microsoft sources
By default Windows 10 will gather updates to the OS not only from Microsoft but from other machines that have the updates. This is enabled by default and automatically adds your workstation as an updater of Windows 10 machines.
We recommend disabling this entirely or at least changing the setting to “PCs on my local network”.
The settings can be changed under Settings, Updates, Windows Updates, Choose how updates are delivered: