Comment by jacquesm

I'd say for commercial hardware it is a near certainty even if you won't ever know until it is much too late.

Realize that many of these manufacturers sell their hardware in and employ companies in highly policed societies. Just the fact that they are allowed to continue to operate implies that they are playing ball and may well have to perform a couple of favors. And that's assuming they are fully aware of what they are shipping, which may not be always the case.

I don't think it is a bad model at all to consider any cell phone to be compromised in multiple ways even though you don't have hard proof.