Password : max 8 digit ?

Somebody complain about hacking password, he changes his password but no
difference with the hacking. So I ask him to tell me from what to what and
this is the response:

scavenger1594u46 to scavenger8634c87

So I think you have the same idea: a camera or a keyboard hacking?

Well!!! NO

The answer: QNX4 is just an 8 digits password security system!

Dream or reality,

I search all the documentation: nothing about a number maximum of digit

Is it a parameter, an option or something that I have to set somewhere?

If it’s like that, why /bin/passwd do not tell to users that they have
entered 8 useless digits?