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 Monoalphabetic substitution - Caesar 5% 7462 15 Arod 4
pas_valide Polyalphabetic substitution - Vigenère 4% 5039 20 Arod 3
pas_valide LFSR - Known plaintext 1% 272 25 Brissouille 1
pas_valide White-Box Cryptography 1% 89 60 Cryptanalyse 2
pas_valide AES-PMAC 1% 9 100 Cryptanalyse 0
pas_valide AES - Fault attack #2 1% 35 80 Cryptanalyse 0
pas_valide AES - Fault attack #1 1% 53 50 Cryptanalyse 1
pas_valide AES - Weaker variant 1% 36 70 Cryptanalyse 0
pas_valide AES - 4 Rounds 1% 109 35 Cryptanalyse 0
pas_valide RSA - Factorisation 2% 2120 25 HacKSpider 4
pas_valide ECDSA - Introduction 1% 63 35 Jrmbt 0
pas_valide ELF64 - PID encryption 3% 4448 15 Lu33Y 10
pas_valide Discrete logarithm problem 1% 523 40 Thanat0s, RFC4949 3
pas_valide Hash - SHA-3 1% 60 75 Revenger 1
pas_valide Known plaintext - XOR 3% 4632 20 Ryscrow 4
pas_valide Pixel Madness 5% 7840 15 Ryscrow 10
pas_valide System - Android lock pattern 3% 3227 20 Silentd 3
pas_valide Polyalphabetic substitution - One Time Pad 1% 265 60 Thanat0s 0
pas_valide AES - CBC - Bit-Flipping Attack 1% 359 25 Tie21 1
pas_valide Code - Pseudo Random Number Generator 2% 1737 20 Tosh 5
pas_valide ECDHE 1% 120 60 Tosh 2
pas_valide AES128 - CTR 1% 394 40 Tosh 1
pas_valide RSA - Padding 1% 136 35 Tosh 0
pas_valide ECDSA - Implementation error 1% 12 100 Tosh 0
pas_valide Encoding - ASCII 26% 40241 5 Xartrick 10
pas_valide Transposition - Rail Fence 2% 3049 20 YellowS4 2
pas_valide RSA - Decipher Oracle 1% 592 25 Zweisamkeit 3
pas_valide RSA - Corrupted key 2 1% 97 40 blackndoor 0
pas_valide RSA - Lee cooper 1% 18 60 blackndoor, Synacktiv 0
pas_valide RSA - Corrupted key 3 1% 35 40 blackndoor 0
pas_valide RSA - Corrupted key 1 1% 139 30 blackndoor 2
pas_valide AES - ECB 1% 1281 25 cez40 4
pas_valide RSA - Multiple recipients 1% 608 40 franb 3
pas_valide RSA - Common modulus 1% 682 30 franb 2
pas_valide Encoding - UU 20% 31891 5 g0uZ 10
pas_valide File - Insecure storage 1 4% 5042 20 g0uZ 5
pas_valide Hash - Message Digest 5 21% 32627 5 g0uZ 6
pas_valide File - PKZIP 4% 5787 15 g0uZ 5
pas_valide Service - Timing attack 1% 1501 25 g0uZ, koma 3
pas_valide Hash - SHA-2 11% 16340 5 koma 4
pas_valide Monoalphabetic substitution - Polybe 2% 1734 25 koma 6
pas_valide Service - Hash length extension attack 1% 445 30 koma 1
pas_valide Service - CBC Padding 1% 638 60 koma 1
pas_valide Shift cipher 7% 9798 10 m31z0nyx 6
pas_valide GEDEFU 1% 306 30 makhno 1
pas_valide Initialisation Vector 1% 949 25 manticore, notfound 4
pas_valide Enigma Machine 1% 110 50 peyman 1
pas_valide RSA - Continued fractions 1% 724 30 sambecks 1

Challenge Results Challenge Results

Pseudo Challenge Lang date
rlich   Encoding - ASCII 22 November 2019 at 00:23
rexipapi   Hash - SHA-2 22 November 2019 at 00:16
Snoil   Encodage - UU 22 November 2019 at 00:13
Snoil   Hash - Message Digest 5 22 November 2019 at 00:11
Snoil   Encodage - ASCII 22 November 2019 at 00:05
Dili   Encodage - ASCII 21 November 2019 at 23:56
mda01   Encodage - UU 21 November 2019 at 23:54
Geographer   RSA - Factorisation 21 November 2019 at 23:50
Bernardo Bemfica   Polyalphabetic substitution - Vigenère 21 November 2019 at 23:48
Bernardo Bemfica   Encoding - UU 21 November 2019 at 23:47