Another one for the list of attacking users....
You're updating the firmware on a server. The firmware is signed, so the attacker cannot outright put their own firmware on your system. The version you're using currently is secure, and the version you want to go to is secure, but there are versions in between that are insecure. All an attacker needs to do is modify the DNS and http stream to feed the firmware with an RCE to you, and then they can directly take over your server.