All your data is owned by your user. If you run a program, it will have access to all your data. Admin or not is irrelevant here.

The keyring is pretty open on Windows, if you know the key you can request anything even if stored by another app. There is a way to lock a secret to a specific app but it's not properly enforced in most versions of Windows.

The only user data that would require admin privilege is that of sandboxed Windows Store applications where even the owner can't access it directly from outside the program and you have to be admin.