Mystery

Challenge Statement

Author: @Michael

Someone sent this to me…

such enigma, such mystery:

rkenr wozec gtrfl obbur bfgma fkgyq ctkvq zeucz hlvwx yyzat zbvns kgyyd sthmi vsifc ovexl zzdqv slyir nwqoj igxuu kdqgr fdbbd njppc mujyy wwcoy

Settings as below:

• 3 Rotor Model
• Rotor 1: VI, Initial: A, Ring A
• Rotor 2: I, Initial: Q, Ring A
• Rotor 3: III, Initial L, Ring A
• Reflector: UKW B
• Plugboard: BQ CR DI EJ KW MT OS PX UZ GH

Solution

This challenge had no attachment to download. So all we have is a cipher text and some “settings”. From my recollection of the movie The Imitation Game I remember that the Enigma machine had rotors and some sort of plugboards.

That and the enigma in the challenge description strongly suggested we have a enigma cipher with key. I don’t have a enigma machine, luckily I found this decoder. I put in the ciphertext, plugged in the setting and got an output.

I don’t know about you all if you noticed. But I missed it. I thought there was another level of cipher to the output and tried a few cipher decoding but none worked. Then I saw it. The message is right there, except white space in the wrong place. I forgot enigma does that. So copying it to a text editor and modifying it I got:

After some text the flag is given. Since enigma doesn’t support anything other than alphabets, I guessed it is implied we have to put the curly braces in the flag. And it was right.