The latest software update, version 188.8.131.52, has blocked rooting using KingRoot, but Fire TV 2 owners wishing to root are in luck because the update has not blocked rbox’s rooting method. You can find my guide for how to root the Fire TV 2 using rbox’s method here. It works on 184.108.40.206 without any modifications. Big thanks to roligov for risking his Fire TV to discover that this method still works. Rest assured that I’ve personally tested the rooting method on a stock 220.127.116.11 Fire TV 2 that had never been rooted and everything went smoothly.
Rooting your Fire TV 2 with this method right now will result in you downgrading to software version 5.0.5 since a pre-rooted ROM for 18.104.22.168 has not been released yet. I have captured the update package for 22.214.171.124 and have passed it along to rbox, so a 126.96.36.199 pre-rooted ROM will probably be released soon. If you’re on 188.8.131.52, you can either block software updates and wait for the pre-rooted 184.108.40.206 ROM to be released before rooting, or root now with the 5.0.5 pre-rooted ROM and update to the 220.127.116.11 pre-rooted ROM when it’s released. Both options are safe to do.
As a reminder, this is the rooting method that requires an A-to-A USB cable, which most people do not have laying around. If you were considering taking advantage of the current Fire TV 2 sale, you can rest assured that rooting is still possible if you receive a device with 18.104.22.168 pre-installed, or can’t get through the intial setup process without updating.