Question: SuperSecure 250 Points Use your team name and generate a valid answer. (File) Summary: xor-chained sha256 and sha512
Tag: crypto
Oct 08
EnoWars CTF – Get On Board (500)
Category: crypto There is also this nice new spaceship in the hangar just waiting for us. Some old-school mobil terminal describes it as: “The Heart of Gold is the sleekest, most advanced, coolest spaceship in the galaxy. “Its stunning good looks mirror its awesome speed and power. It is powered by the revolutionary new Infinite …
Oct 01
rwth2011 CTF – ps3game
This service was on exploiting, understanding udp protocol and process of sign data. ps3game files Summary: reversing, crypto, rsa, tea hash, udp sign
Sep 22
hack.lu CTF 2011 Wipe out the Klingons (400)
Category: crypto We already made it. The evil Klingons agression is nearly fended. But their final mothership is well protected and even sacrifing a huge number of battleships caused only minor damage. Spies told us an unclear message caused most technical operators and the commander to leave the ship. Unfortunately we are unable to locate …
Sep 21
hack.lu CTF 2011 Spy Aboard! (300)
Category: crypto We have a spy aboard! For around 5 minutes ago we intercepted an encrypted transmission to an enemy outpost. It seems like we interrupted the mole in the act because we found an open transmission program on our terminals. We are 100% sure that he sent the position of our fleet to the …
Sep 21
hack.lu CTF 2011 Simplexor (200)
Category: crypto To get a better security we deceided to encrypt our most secret document with the secure xor-algorithm. Unfortunately we lost the key. Now we are sad. Can you help us recovering the key? Download Summary: recovering multibyte xor-key, using autocorrelation
Apr 04
Nuit du hack 2011 CTF Crypto 300
Crypto300 (150 pts.) source Python source code is very clear and concise, and could sometimes bring out lots of clues. This is particularly true for this challenge. Summary: key exchange algorithm based on permutations (braid based cryptography), has some vulnerabilities
Mar 08
Codegate CTF 2011 Crypto 400
The attacker got a secret! File Summary: Padding oracle attack analysis
Mar 07
Codegate CTF 2011 Mini writeups
Some mini writeups on Codegate 2011 Prequals: Issue100,200, Net100,200, Crypto100,200.
Mar 07
Codegate CTF 2011 Crypto300 Writeup
Description: we are investigating an illegal online gambling site. To find any evidence to support for illegal gambling, we must access the oracle database with administrator privileges. The suspect says that he does not know the administrator password, but we know for sure that he is lying. The password is estimated to be longer than …
Jan 20
Padocon CTF 2011 Binary500 Writeup (300)
The challenge consists of a windows binary and connection details: HOST : 168.188.130.216 PORT : 888 Binary (Daemon.exe) Summary: reversing the algorithm with some encryption and coding a client
Oct 31
Hack.lu 2010 CTF #16 (Rattlesnake’s Riddle) writeup
Solve this riddle to impress Captain Rattlesnake! download The .pyc file is a byte-compiled python code, and there is a wonderful tool called uncompyle to deal with it. $ decompyle secret.pyc > secret.py The decompyled file: 1. Takes 3 arguments 2. Checks 2nd to be 1337 3. Calculates ‘token‘ value, which is 11111112671 4. After some …
Oct 30
Hack.lu 2010 CTF Challenge #8 Writeup
Sad Little Pirate (150) Our sad little pirate haes lost his password. It is known that the pirate has just one hand left; his left hand. So the paessword input is quite limited. Also he can still remember that the plaintext started with “674e2” and his password with “wcwteseawx” Please help the sad pirate finding …
Oct 30
Hack.lu 2010 CTF Challenge #7 Writeup
Breiers Deathmatch (150) Schnuce Breier has challenged you to a cryptographer’s deathmatch. Connect to pirates.fluxfingers.net 8007/tcp and get the secret number. $ nc pirates.fluxfingers.net 8007 Hi. This is your friendly ‘Decryption Oracle’ We have implemented a well-known public-key cryptosystem. Guess which ;) Modulo: 5628290459057877291809182450381238927697314822133923421169378 062922140081498734424133112032854812341 Generator: 99 Public Key: 135744434201778324839308712462911647727754874814096844915 5264250239122362719894347099351280643528244 Ciphertext: (44750535504622985677351849167148532593337860047243938284 03819968944371696234280482660523326406427034, 40867215175893797288404 …
Sep 21
Leet More 2010 LameHackers writeup
Category: crypto Greetings from LameHackers Inc.! We have hacked into the internal Pentagon computer system and managed to steal their text-file-where-they-keep-the-root-password. But the password doesn’t work :( Can you help us? File Ok, first of all I want to thank everyone participating in Leet More 2010, it was a cool competition, though on wednesday. And …