Cryptanalysis

Break encryption algorithms

These tests will allow you to hone your cryptography skills. You will be faced with an encoded data. The challenge is to find the type of encoding or encryption and revert it back to find the solution.

Prerequisites:

- Knowledge of most common encoding formats.
- Knowledge of most common hash algorithms and ciphers.
- Knowledge of a scripting language.

 48 Challenges

Results Name Validations Number of points  Explanation for the scores Difficulty  Difficulty Author Note   Notation Solution
pas_valide Polyalphabetic substitution - One Time Pad 1% 271 60 Thanat0s 0
pas_valide AES - ECB 1% 1404 25 cez40 4
pas_valide RSA - Corrupted key 2 1% 115 40 blackndoor 0
pas_valide GEDEFU 1% 330 30 makhno 1
pas_valide RSA - Corrupted key 1 1% 163 30 blackndoor 2
pas_valide File - PKZIP 4% 6334 15 g0uZ 6
pas_valide AES-PMAC 1% 10 100 Cryptanalyse 0
pas_valide RSA - Factorisation 2% 2313 25 HacKSpider 5
pas_valide LFSR - Known plaintext 1% 345 25 Brissouille 1
pas_valide Discrete logarithm problem 1% 568 40 Thanat0s, RFC4949 3
pas_valide Transposition - Rail Fence 2% 3350 20 YellowS4 3
pas_valide Monoalphabetic substitution - Caesar 5% 8105 15 Arod 4
pas_valide Hash - SHA-2 11% 17762 5 koma 4
pas_valide Enigma Machine 1% 118 50 peyman 1
pas_valide Pixel Madness 5% 8528 15 Ryscrow 10
pas_valide Shift cipher 7% 10687 10 m31z0nyx 7
pas_valide AES - Fault attack #2 1% 48 80 Cryptanalyse 1
pas_valide AES - Weaker variant 1% 42 70 Cryptanalyse 1
pas_valide ECDSA - Implementation error 1% 16 100 Tosh 0
pas_valide File - Insecure storage 1 4% 5355 20 g0uZ 5
pas_valide Hash - SHA-3 1% 63 75 Revenger 1
pas_valide Polyalphabetic substitution - Vigenère 4% 5481 20 Arod 3
pas_valide Monoalphabetic substitution - Polybe 2% 1900 25 koma 6
pas_valide AES - CBC - Bit-Flipping Attack 1% 445 25 Tie21 1
pas_valide Initialisation Vector 1% 1038 25 manticore, notfound404 5
pas_valide AES - 4 Rounds 1% 124 35 Cryptanalyse 0
pas_valide Service - Timing attack 1% 1583 25 g0uZ, koma 3
pas_valide RSA - Multiple recipients 1% 689 40 franb 3
pas_valide AES128 - CTR 1% 421 40 Tosh 1
pas_valide ELF64 - PID encryption 3% 4768 15 Lu33Y 10
pas_valide System - Android lock pattern 3% 3533 20 Silentd 4
pas_valide Service - CBC Padding 1% 710 60 koma 1
pas_valide Known plaintext - XOR 3% 5019 20 Ryscrow 5
pas_valide AES - Fault attack #1 1% 67 50 Cryptanalyse 1
pas_valide RSA - Lee cooper 1% 40 60 blackndoor, Synacktiv 0
pas_valide RSA - Decipher Oracle 1% 689 25 Zweisamkeit 3
pas_valide ECDSA - Introduction 1% 84 35 Jrmbt 0
pas_valide Service - Hash length extension attack 1% 488 30 koma 1
pas_valide Code - Pseudo Random Number Generator 2% 1886 20 Tosh 5
pas_valide RSA - Continued fractions 1% 785 30 sambecks 1
pas_valide RSA - Padding 1% 146 35 Tosh 0
pas_valide White-Box Cryptography 1% 92 60 Cryptanalyse 3
pas_valide Encoding - UU 21% 34532 5 g0uZ 10
pas_valide Hash - Message Digest 5 21% 35143 5 g0uZ 6
pas_valide ECDHE 1% 127 60 Tosh 2
pas_valide Encoding - ASCII 26% 43774 5 Xartrick 10
pas_valide RSA - Common modulus 1% 783 30 franb 2
pas_valide RSA - Corrupted key 3 1% 55 40 blackndoor 0

Challenge Results Challenge Results

Pseudo Challenge Lang date
koala   Monoalphabetic substitution - Polybe 25 February 2020 at 23:13
koala   Service - Timing attack 25 February 2020 at 23:12
koala   Polyalphabetic substitution - Vigenère 25 February 2020 at 23:05
cdtorrest   Pixel Madness 25 February 2020 at 22:54
cdtorrest   Hash - Message Digest 5 25 February 2020 at 22:51
nikumaru   Encodage - UU 25 February 2020 at 22:51
Hiko   Vecteur d’initialisation 25 February 2020 at 22:47
Raefko   ELF64 - Chiffrement avec le PID 25 February 2020 at 22:47
cdtorrest   Encoding - UU 25 February 2020 at 22:46
madmoose_   File - Insecure storage 1 25 February 2020 at 22:45