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% 44932 5 Xartrick 10
pas_valide Encoding - UU 21% 35473 5 g0uZ 10
pas_valide Hash - Message Digest 5 21% 36066 5 g0uZ 6
pas_valide Hash - SHA-2 11% 18250 5 koma 4
pas_valide Shift cipher 7% 11088 10 m31z0nyx 7
pas_valide Pixel Madness 5% 8796 15 Ryscrow 10
pas_valide ELF64 - PID encryption 3% 4897 15 Lu33Y 10
pas_valide File - PKZIP 4% 6567 15 g0uZ 6
pas_valide Monoalphabetic substitution - Caesar 5% 8358 15 Arod 4
pas_valide Known plaintext - XOR 3% 5144 20 Ryscrow 5
pas_valide Code - Pseudo Random Number Generator 2% 1948 20 Tosh 5
pas_valide File - Insecure storage 1 4% 5482 20 g0uZ 5
pas_valide Polyalphabetic substitution - Vigenère 4% 5671 20 Arod 3
pas_valide System - Android lock pattern 3% 3630 20 Silentd 4
pas_valide Transposition - Rail Fence 2% 3446 20 YellowS4 3
pas_valide AES - CBC - Bit-Flipping Attack 1% 494 25 Tie21 1
pas_valide AES - ECB 1% 1452 25 cez40 4
pas_valide LFSR - Known plaintext 1% 370 25 Brissouille 1
pas_valide RSA - Factorisation 2% 2381 25 HacKSpider 5
pas_valide RSA - Decipher Oracle 1% 727 25 Zweisamkeit 3
pas_valide Service - Timing attack 1% 1619 25 g0uZ, koma 3
pas_valide Monoalphabetic substitution - Polybe 2% 1962 25 koma 6
pas_valide Initialisation Vector 1% 1075 25 manticore, notfound404 5
pas_valide GEDEFU 1% 343 30 makhno 1
pas_valide RSA - Corrupted key 1 1% 170 30 blackndoor 2
pas_valide RSA - Continued fractions 1% 809 30 sambecks 1
pas_valide RSA - Common modulus 1% 823 30 franb 2
pas_valide Service - Hash length extension attack 1% 507 30 koma 1
pas_valide AES - 4 Rounds 1% 127 35 Cryptanalyse 0
pas_valide ECDSA - Introduction 1% 99 35 Jrmbt 1
pas_valide RSA - Padding 1% 151 35 Tosh 0
pas_valide RSA - Signature 1% 31 35 stan1slas 0
pas_valide AES128 - CTR 1% 424 40 Tosh 1
pas_valide Discrete logarithm problem 1% 575 40 Thanat0s, RFC4949 3
pas_valide RSA - Corrupted key 2 1% 117 40 blackndoor 0
pas_valide RSA - Corrupted key 3 1% 58 40 blackndoor 0
pas_valide RSA - Multiple recipients 1% 714 40 franb 3
pas_valide AES - Fault attack #1 1% 70 50 Cryptanalyse 1
pas_valide Enigma Machine 1% 120 50 peyman 1
pas_valide ECDHE 1% 129 60 Tosh 2
pas_valide RSA - Lee cooper 1% 44 60 blackndoor, Synacktiv 0
pas_valide Service - CBC Padding 1% 733 60 koma 1
pas_valide Polyalphabetic substitution - One Time Pad 1% 273 60 Thanat0s 0
pas_valide White-Box Cryptography 1% 92 60 Cryptanalyse 3
pas_valide AES - Weaker variant 1% 43 70 Cryptanalyse 1
pas_valide Hash - SHA-3 1% 73 75 Revenger 1
pas_valide AES - Fault attack #2 1% 49 80 Cryptanalyse 1
pas_valide AES-PMAC 1% 11 100 Cryptanalyse 0
pas_valide ECDSA - Implementation error 1% 16 100 Tosh 0

Challenge Results Challenge Results

Pseudo Challenge Lang date
JOE   Hash - SHA-2 4 April 2020 at 03:16
xdjibi   RSA - Factorisation 4 April 2020 at 02:09
Brain_out   Encodage - UU 4 April 2020 at 00:43
lenordistefou   Code - Pseudo Random Number Generator 4 April 2020 at 00:41
juanpe   Hash - Message Digest 5 3 April 2020 at 23:55
juanpe   Encoding - UU 3 April 2020 at 23:51
xdjibi   Service - Timing attack 3 April 2020 at 23:49
juanpe   Encoding - ASCII 3 April 2020 at 23:49
tusita-   Encoding - UU 3 April 2020 at 23:46
Mayus   RSA - Modules communs 3 April 2020 at 22:42