I contacted Petnet (http://petnet.io) and they provided the following response, with a link to Electric Imp's official response. It seems Electric Imp is used by many IoT devices.
Josh Bullock (Petnet)
Nov 2, 09:25 PDT
Hello,
Thank you for reaching out. The platform isn’t vulnerable to KRACK (or many other common attacks). An attacker cannot interfere with, decrypt, or impersonate, valid imp traffic which in turn means they cannot interfere with, decrypt, or impersonate valid Petnet traffic.
I contacted Petnet (http://petnet.io) and they provided the following response, with a link to Electric Imp's official response. It seems Electric Imp is used by many IoT devices.