[Full-disclosure] Re: defeating voice captchas

[ol]

> >
> > (*) Of course, it's better to use sound sources that are hard to
> > identify, and are ideally not available to the attacker; else he could
> > obtain the same sounds and subtract them from the audio. I think some
> > random pitch shifting (tremolo) would help against this.
>
> OK. Use voice recognition.


We all know how well those work! Using IVR systems which reliably detect
what I say when I speak slowly and clearly without sounding like Basil
Faulty speaking to Manuel are non existent. So surely the reverse would be
true of any voice recognition system applied to voice captchas.....