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.

 50 Challenges

Results Name Validations Number of points  Explanation for the scores Difficulty   Difficulty Author Note  Notation Solution
pas_valide Encoding - ASCII 26% 54132 5 Xartrick 10
pas_valide Hash - Message Digest 5 21% 42732 5 g0uZ 6
pas_valide Hash - SHA-2 11% 22008 5 koma 4
pas_valide Encoding - UU 21% 42416 5 g0uZ 10
pas_valide Shift cipher 7% 13429 10 m31z0nyx 9
pas_valide File - PKZIP 4% 7914 15 g0uZ 6
pas_valide Monoalphabetic substitution - Caesar 5% 9986 15 Arod 4
pas_valide ECDSA - Introduction 1% 141 35 Jrmbt 2
pas_valide RSA - Continued fractions 1% 952 30 sambecks 1
pas_valide RSA - Common modulus 1% 1026 30 franb 2
pas_valide Service - Hash length extension attack 1% 644 30 koma 1
pas_valide AES - 4 Rounds 1% 169 35 Cryptanalyse 0
pas_valide Discrete logarithm problem 1% 703 40 Thanat0s, RFC4949 3
pas_valide RSA - Padding 1% 184 35 Tosh 0
pas_valide RSA - Signature 1% 74 35 s4r 1
pas_valide AES128 - CTR 1% 478 40 Tosh 2
pas_valide Initialisation Vector 1% 1278 25 manticore, notfound404 5
pas_valide RSA - Corrupted key 2 1% 160 40 blackndoor 0
pas_valide RSA - Corrupted key 3 1% 80 40 blackndoor 0
pas_valide RSA - Multiple recipients 1% 853 40 franb 3
pas_valide GEDEFU 1% 417 30 makhno 1
pas_valide RSA - Corrupted key 1 1% 240 30 blackndoor 2
pas_valide Twisted secret 1% 134 25 NonStandardModel 1
pas_valide System - Android lock pattern 3% 4364 20 Silentd 4
pas_valide Pixel Madness 6% 10534 15 Ryscrow 10
pas_valide Monoalphabetic substitution - Polybe 2% 2354 25 koma 6
pas_valide Known plaintext - XOR 3% 5966 20 Ryscrow 5
pas_valide Code - Pseudo Random Number Generator 2% 2321 20 Tosh 5
pas_valide File - Insecure storage 1 3% 6227 20 g0uZ 6
pas_valide Polyalphabetic substitution - Vigenère 4% 6614 20 Arod 3
pas_valide ELF64 - PID encryption 3% 5601 15 Lu33Y 10
pas_valide Transposition - Rail Fence 2% 4038 20 YellowS4 3
pas_valide AES - ECB 1% 1678 25 cez40 4
pas_valide LFSR - Known plaintext 1% 511 25 Brissouille 1
pas_valide RSA - Factorisation 2% 2828 25 HacKSpider 5
pas_valide RSA - Decipher Oracle 1% 966 25 Zweisamkeit 3
pas_valide Service - Timing attack 1% 1861 25 g0uZ, koma 4
pas_valide AES - CBC - Bit-Flipping Attack 1% 756 25 Tie21 2
pas_valide White-Box Cryptography 1% 117 60 Cryptanalyse 3
pas_valide AES - Fault attack #2 1% 67 80 Cryptanalyse 1
pas_valide Hash - SHA-3 1% 86 75 Revenger 1
pas_valide AES - Weaker variant 1% 77 70 Cryptanalyse 1
pas_valide ECDHE 1% 153 60 Tosh 2
pas_valide Polyalphabetic substitution - One Time Pad 1% 306 60 Thanat0s 0
pas_valide Service - CBC Padding 1% 834 60 koma 1
pas_valide RSA - Lee cooper 1% 74 60 blackndoor, Synacktiv 1
pas_valide Enigma Machine 1% 157 50 peyman 2
pas_valide AES - Fault attack #1 1% 91 50 Cryptanalyse 1
pas_valide AES-PMAC 1% 12 100 Cryptanalyse 0
pas_valide ECDSA - Implementation error 1% 22 100 Tosh 0

Challenge Results Challenge Results

Pseudo Challenge Lang date
domajo   Encoding - UU 28 February 2021 at 11:30
domajo   Encoding - ASCII 28 February 2021 at 11:28
EF115_bmkiet   AES - CBC - Bit-Flipping Attack 28 February 2021 at 11:20
Kemkeb71   Shift cipher 28 February 2021 at 11:13
Kemkeb71   Hash - SHA-2 28 February 2021 at 11:13
Kemkeb71   Hash - Message Digest 5 28 February 2021 at 11:12
Kemkeb71   Encoding - UU 28 February 2021 at 11:12
Kemkeb71   Encoding - ASCII 28 February 2021 at 11:12
BouBooo   Encodage - ASCII 28 February 2021 at 10:57
white   Hash - Message Digest 5 28 February 2021 at 09:01