Challenges: Crypto

Splyt [96 points, 105 solves]

Bob splitted a secret and gave some pieces of it to some of his friends. We managed to convince Eve and Chris to give us their shares.

Download: splyt.tgz

Rock Solid Cryptography [33 points, 184 solves]

7º 2' 34.46" W 54º 41' 54.28" N

Pay attention: the flag is not in the standard format

Update: Flag format: all uppercase

Download: rocksolid.jpg.gz

Back to the Exploit [0 solves]

We got these misterious files from a weirdo claiming to be a scientist...

nc btte.chall.polictf.it 31336

nc btte.chall.polictf.it 31337

Update: Just to be clear, port 31336 and 31337 are different services, you need to use both to solve the challenge.

Hint: Have You already figured out the date the starting message was received?

Download: btte.tgz

(server-side sources not released, sorry)

Super-secure custom One Time Pad! [500 points, 1 solve]

Somebody managed to grab some packets from our network, but we're using a custom super-shiny cryptosystem which is unbreakable!

Download: otp.tbz2

Lucky Consecutive Guessing [301 points, 32 solves]

We implemented a random number generator. We've heard that rand()'s 32 bit seeds can be easily cracked, so we stayed on the safe side.

nc lucky.chall.polictf.it 31337

Download: lucky.py.gz