Saturday, 5 April 2014

Nuit de Hack Quals - 2014 Carbonara

This was easy and i actually over thought it..
Question :

the ciphertext was : "%96 7=28 7@C E9:D 492= :D iQx>A6C2E@C xF=:FD r26D2C s:GFDQ]"

My first approach:
substitution by looking at

":" - "i"
"D" - "s"

after which with the help of this (which i just guessed as it was a 2 letter string and my guess was it would be "is")
decoding which i got
i was stuck with the letter x actually..Later my friend told that it was a rot-47 :-D all my work in vain..i got the string as :
The flag for this chal is :"Imperator Iulius Caesar Divus".

Flag : Imperator Iulius Caesar Divus 

Nuit de Hack Quals -2014 Here Kitty Kitty!

Not much flags this time too..Managed to get 3 of them and will write however i got it.
Mirror Link :

So well first thing we would think of is audacity.Lets try our luck..You get a weird waveform.I just zoomed in to see the waveform.I got a view of Morse code,before which i thought it was a binary . Dont zoom in much coz you would over think as binary numbers.It would look like this :

Note down accordingly and you would get this Morse code

..... -... -.-. ----. ..--- ..... -.... ....- ----. -.-. -... ----- .---- ---.. ---.. ..-. ..... ..--- . -.... .---- --... -.. --... ----- ----. ..--- ----. .---- ----. .---- -.-.

Decoding which will give a md5 hash : 5BC925649CB0188F52E617D70929191C
As the flag was case sensitive and was lowercase so the flag would be : 5bc925649cb0188f52e617d70929191c

Flag : 5bc925649cb0188f52e617d70929191c