A lot of controversy has arisen from the Windows 10 upgrade. Once installed, your wi-fi connection can be shared by most anyone, even without your knowledge. To be sure, there are some controls and the free and open access can be turned off but most Windows 10 users probably are not aware of the problems. Any upgrade made by simply taking the defaults becomes an open target for hackers and identity thieves.
Wi-Fi Sense, a little known (and controversial) feature of Windows 10, lets any of your friends and contacts use your Wi-Fi network , without even having to ask you for permission or a password.
Matthew Hughes discusses the pros and cons of Windows 10’s Wi-Fi Sense at http://www.makeuseof.com/tag/windows-10s-wifi-sense-feature-represent-security-risk.