Eddy, I don't agree with you, it's not depend of router's firmware, you just need to have a dictionary with default or weak passwords (smth. like 1234 or qwerty) and check if this password matches.
It's one of the main goal of HNS to check if your home network is secured, but if I have a default password and HNS will say your home network is well configured users will think they're secured.