Related link:
http://www.leviathansecurity.com/blog/the-case-of-the-modified-binaries/
There is no escape. The internet is a rigged game.
Use a virtual machine.
It strikes me that no one should be updating their Operating System software using an anonymized TOR connection. . . which is what a TOR is used for. It is a network for persons who want to connect to the Internet anonymously. If you want to update your software, connect without the TOR. Then return to your secret surfing after your software has been updated.
Perhaps software pirates might want this for stolen software? If so, they might deserve what they get.
Shocking.
Or maybe, well duh.
It was probably a government node.
It's good that the modified Windows update files failed their integrity checks and were not installed, but they should never have been downloaded at all.
I just checked, and Windows fixit file downloads are from http://diagnostics.support.microsoft.com. That's not even an https connection.