I haven’t been able to find any discussion whatsoever on this device. It seems to be the only phone that the EU has classified as usable for the “SECRET” [confidentiality level](https://en.wikipedia.org/wiki/Classified_information#International_organisations).
Technical documentation on this phone does not seem to be publicly available. No whitepapers or anything. Does anyone know if this phone is actually secure? How it works? Or if it’s just traditional government contractor showboating?
It seems that there is a sort of custom hardware security token that needs to be plugged into the phone before beginning a call. My guess is that this functions like any other hardware security token, and the phone itself is just a barebones operating system + feature phone in order to reduce attack surface.
Perhaps there is some attestation between the token and the phone, to verify the integrity of either against an evil maid attack? Really, I couldn’t find any details.