I'm actually a bit confused about how this is a "golden key" problem (if I understand what that means). As far as I can tell, the problem here is that there's

I'm actually a bit confused about how this is a "golden key" problem (if I understand what that means). As far as I can tell, the problem here is that there's a signed policy that was intended for newer versions of Windows, but is also interpreted by older versions of Windows as a valid policy with a different meaning. On Win10 1607 it means "under such-and-such conditions, merge these additional rules into the already applied policy" and on older Windows it just means "apply this policy". But the only key here in both cases is Microsoft's regular signing key. Which I guess could be considered a kind of golden key/backdoor/whatever in itself - just as in the recent Apple vs. FBI standoff you could say the fact that Apple had the technical ability to sign and install a hacked OS was a backdoor to begin with - but that doesn't seem to be what people mean.