Computerworld - https://www.computerworld.com/article/3277946/apple-ios/what-is-apple-hiding-with-ios-11-4.html#tk.rss_all
‘Details available soon’
If you did you’ll have been disappointed.
Apple hasn’t disclosed details concerning the security content of the new software. It hasn’t revealed anything concerning USB Restricted Mode, which apparently makes it harder for people to hack into your device.