Description
This challenge provides a file that sounds like sombody pressing a bunch of numbers into a phone.
Walkthrough
To solve this challenge we can google how to decode phone noises. Doing this we’ll find that the noises are encoded using a protocal called DTMF. Poking around we can find a tool called dtmf-decoder. Install it and run dtmf audio.wav to get the numbers 469096804666202280545308428.
This isn’t a traditional phone number so maybe its encoded some way? Useing context clues we can tell that there are references to the early 2000s maybe this is using a phone that sends messages like a nokia with a limited number of buttons. Doing some research we can find out that phones back then would use predictive typing to guess the words you were typing as you were typing them to help decrease the amount of time you were punching in numbers. This predictive text technology was called t9 which conviently has a decover availabl here.
If we plug in our number number we’ll get the following options to chose from:
Doing some guessing and checking we’ll find that the final flag is texsaw{howyougonnaactlikethat}.