cryptoquizz

Crypto - 50 Points

Hello, young hacker. Are you ready to fight rogue machines ? Now, you’ll have to prove us that you are a genuine cryptographer.

Running on quizz.teaser.insomnihack.ch:1031

Writeup

I’ve started connecting to the service with netcat

nc quizz.teaser.insomnihack.ch 1031

The server reply with this text:

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~ Hello, young hacker. Are you ready to fight rogue machines ?    ~~
~~ Now, you'll have to prove us that you are a genuine             ~~
~~ cryptographer.                                                  ~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~ What is the birth year of Ralph Merkle ?
Connection closed by Host

Wow, this server have very very low timeout!

So I’ve searched up for Ralph Merkle birthyear (1952) and made a little script that open the connection and reply with that printing the response. This was the output

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~ Hello, young hacker. Are you ready to fight rogue machines ?    ~~
~~ Now, you'll have to prove us that you are a genuine             ~~
~~ cryptographer.                                                  ~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~ What is the birth year of Alan Turing ?
1952
Connection closed by Host

Oh! The name is randomized so I can’t reply directly with Merkle’s birthyear. So I have to read the question, check the date and reply.

I’ve wrote a script that open the connection read the question and store the cryptographer’s name. Once I had many cryptographers birthyears I’ve develop this script that reply accordingly.

Here you can download the cryptoquizz_solver.py

And here the final session after 52 stored cryptographers

[+] Opening connection to quizz.teaser.insomnihack.ch on port 1031: Done
~~ What is the birth year of Horst Feistel ?
1915
~~ What is the birth year of Tatsuaki Okamoto ?
1952
~~ What is the birth year of Shafi Goldwasser ?
1958
~~ What is the birth year of Dan Boneh ?
1969
~~ What is the birth year of Ralph Merkle ?
1952
~~ What is the birth year of Lars Knudsen ?
1962
~~ What is the birth year of David Naccache ?
1967
~~ What is the birth year of Alan Turing ?
1912
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~ OK, young hacker. You are now considered to be a ~~
~~ INS{GENUINE_CRYPTOGRAPHER_BUT_NOT_YET_A_PROVEN_SKILLED_ONE} ~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~