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.

 49 Challenges

Results Name Validations Number of points  Explanation for the scores Difficulty  Difficulty Author Note  Notation Solution
pas_valide Encoding - ASCII 26% 47489 5 Xartrick 10
pas_valide Encoding - UU 21% 37406 5 g0uZ 10
pas_valide Hash - Message Digest 5 21% 37905 5 g0uZ 6
pas_valide Hash - SHA-2 11% 19330 5 koma 4
pas_valide Shift cipher 7% 11775 10 m31z0nyx 8
pas_valide Pixel Madness 6% 9290 15 Ryscrow 10
pas_valide ELF64 - PID encryption 3% 5096 15 Lu33Y 10
pas_valide File - PKZIP 4% 6979 15 g0uZ 6
pas_valide Monoalphabetic substitution - Caesar 5% 8914 15 Arod 4
pas_valide Known plaintext - XOR 3% 5367 20 Ryscrow 5
pas_valide Code - Pseudo Random Number Generator 2% 2047 20 Tosh 5
pas_valide File - Insecure storage 1 4% 5686 20 g0uZ 5
pas_valide Polyalphabetic substitution - Vigenère 4% 5986 20 Arod 3
pas_valide System - Android lock pattern 3% 3857 20 Silentd 4
pas_valide Transposition - Rail Fence 2% 3630 20 YellowS4 3
pas_valide AES - CBC - Bit-Flipping Attack 1% 574 25 Tie21 1
pas_valide AES - ECB 1% 1516 25 cez40 4
pas_valide LFSR - Known plaintext 1% 425 25 Brissouille 1
pas_valide RSA - Factorisation 2% 2514 25 HacKSpider 5
pas_valide RSA - Decipher Oracle 1% 805 25 Zweisamkeit 3
pas_valide Service - Timing attack 1% 1710 25 g0uZ, koma 4
pas_valide Monoalphabetic substitution - Polybe 2% 2094 25 koma 6
pas_valide Initialisation Vector 1% 1140 25 manticore, notfound404 5
pas_valide GEDEFU 1% 376 30 makhno 1
pas_valide RSA - Corrupted key 1 1% 194 30 blackndoor 2
pas_valide RSA - Continued fractions 1% 855 30 sambecks 1
pas_valide RSA - Common modulus 1% 881 30 franb 2
pas_valide Service - Hash length extension attack 1% 548 30 koma 1
pas_valide AES - 4 Rounds 1% 141 35 Cryptanalyse 0
pas_valide ECDSA - Introduction 1% 113 35 Jrmbt 1
pas_valide RSA - Padding 1% 160 35 Tosh 0
pas_valide RSA - Signature 1% 55 35 s4r 1
pas_valide AES128 - CTR 1% 446 40 Tosh 1
pas_valide Discrete logarithm problem 1% 612 40 Thanat0s, RFC4949 3
pas_valide RSA - Corrupted key 2 1% 134 40 blackndoor 0
pas_valide RSA - Corrupted key 3 1% 67 40 blackndoor 0
pas_valide RSA - Multiple recipients 1% 759 40 franb 3
pas_valide AES - Fault attack #1 1% 76 50 Cryptanalyse 1
pas_valide Enigma Machine 1% 137 50 peyman 2
pas_valide ECDHE 1% 138 60 Tosh 2
pas_valide RSA - Lee cooper 1% 55 60 blackndoor, Synacktiv 0
pas_valide Service - CBC Padding 1% 765 60 koma 1
pas_valide Polyalphabetic substitution - One Time Pad 1% 280 60 Thanat0s 0
pas_valide White-Box Cryptography 1% 100 60 Cryptanalyse 3
pas_valide AES - Weaker variant 1% 46 70 Cryptanalyse 1
pas_valide Hash - SHA-3 1% 79 75 Revenger 1
pas_valide AES - Fault attack #2 1% 53 80 Cryptanalyse 1
pas_valide AES-PMAC 1% 11 100 Cryptanalyse 0
pas_valide ECDSA - Implementation error 1% 18 100 Tosh 0

Challenge Results Challenge Results

Pseudo Challenge Lang date
NeyZ   Encodage - UU 3 July 2020 at 12:12
NeyZ   Encodage - ASCII 3 July 2020 at 12:07
chain_aaa   File - Insecure storage 1 3 July 2020 at 11:47
chain_aaa   File - PKZIP 3 July 2020 at 11:44
Arkan   Hash - Message Digest 5 3 July 2020 at 11:19
Arkan   Encodage - UU 3 July 2020 at 11:17
Arkan   Encodage - ASCII 3 July 2020 at 11:15
Ryok   Hash - Message Digest 5 3 July 2020 at 09:22
BliiTzZ_   Chiffrement par décalage 3 July 2020 at 09:21
Ryok   Encodage - UU 3 July 2020 at 09:20