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 Monoalphabetic substitution - Caesar 5% 8943 15 Arod 4
pas_valide Polyalphabetic substitution - Vigenère 4% 5998 20 Arod 3
pas_valide LFSR - Known plaintext 1% 428 25 Brissouille 1
pas_valide White-Box Cryptography 1% 101 60 Cryptanalyse 3
pas_valide AES-PMAC 1% 11 100 Cryptanalyse 0
pas_valide AES - Fault attack #2 1% 53 80 Cryptanalyse 1
pas_valide AES - Fault attack #1 1% 76 50 Cryptanalyse 1
pas_valide AES - Weaker variant 1% 46 70 Cryptanalyse 1
pas_valide AES - 4 Rounds 1% 143 35 Cryptanalyse 0
pas_valide RSA - Factorisation 2% 2521 25 HacKSpider 5
pas_valide ECDSA - Introduction 1% 114 35 Jrmbt 1
pas_valide ELF64 - PID encryption 3% 5109 15 Lu33Y 10
pas_valide Discrete logarithm problem 1% 612 40 Thanat0s, RFC4949 3
pas_valide Hash - SHA-3 1% 79 75 Revenger 1
pas_valide Known plaintext - XOR 3% 5385 20 Ryscrow 5
pas_valide Pixel Madness 6% 9315 15 Ryscrow 10
pas_valide System - Android lock pattern 3% 3867 20 Silentd 4
pas_valide Polyalphabetic substitution - One Time Pad 1% 280 60 Thanat0s 0
pas_valide AES - CBC - Bit-Flipping Attack 1% 576 25 Tie21 1
pas_valide Code - Pseudo Random Number Generator 2% 2052 20 Tosh 5
pas_valide ECDHE 1% 139 60 Tosh 2
pas_valide AES128 - CTR 1% 446 40 Tosh 1
pas_valide RSA - Padding 1% 160 35 Tosh 0
pas_valide ECDSA - Implementation error 1% 18 100 Tosh 0
pas_valide Encoding - ASCII 26% 47642 5 Xartrick 10
pas_valide Transposition - Rail Fence 2% 3640 20 YellowS4 3
pas_valide RSA - Decipher Oracle 1% 809 25 Zweisamkeit 3
pas_valide RSA - Corrupted key 2 1% 134 40 blackndoor 0
pas_valide RSA - Lee cooper 1% 55 60 blackndoor, Synacktiv 0
pas_valide RSA - Corrupted key 3 1% 67 40 blackndoor 0
pas_valide RSA - Corrupted key 1 1% 194 30 blackndoor 2
pas_valide AES - ECB 1% 1518 25 cez40 4
pas_valide RSA - Common modulus 1% 884 30 franb 2
pas_valide RSA - Multiple recipients 1% 760 40 franb 3
pas_valide Encoding - UU 21% 37520 5 g0uZ 10
pas_valide Hash - Message Digest 5 21% 38027 5 g0uZ 6
pas_valide Service - Timing attack 1% 1713 25 g0uZ, koma 4
pas_valide File - Insecure storage 1 4% 5701 20 g0uZ 5
pas_valide File - PKZIP 4% 7005 15 g0uZ 6
pas_valide Monoalphabetic substitution - Polybe 2% 2098 25 koma 6
pas_valide Service - CBC Padding 1% 766 60 koma 1
pas_valide Service - Hash length extension attack 1% 552 30 koma 1
pas_valide Hash - SHA-2 11% 19391 5 koma 4
pas_valide Shift cipher 7% 11814 10 m31z0nyx 8
pas_valide GEDEFU 1% 378 30 makhno 1
pas_valide Initialisation Vector 1% 1141 25 manticore, notfound404 5
pas_valide Enigma Machine 1% 139 50 peyman 2
pas_valide RSA - Signature 1% 55 35 s4r 1
pas_valide RSA - Continued fractions 1% 857 30 sambecks 1

Challenge Results Challenge Results

Pseudo Challenge Lang date
Hiboo   Encodage - ASCII 10 July 2020 at 22:59
Hiteek   Hash - SHA-2 10 July 2020 at 21:03
ctf-new   Hash - SHA-2 10 July 2020 at 21:02
panha   Encoding - ASCII 10 July 2020 at 20:12
BRGAJ   Hash - Message Digest 5 10 July 2020 at 20:01
ctf-new   Hash - Message Digest 5 10 July 2020 at 19:53
BRGAJ   Encoding - ASCII 10 July 2020 at 19:53
A1CY0N   Machine Enigma 10 July 2020 at 19:44
giox98   Hash - SHA-2 10 July 2020 at 19:39
testCurso   Hash - SHA-2 10 July 2020 at 19:30