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Cryptography

Scrumbled and encrypted text
Whatever happen, google is your friend. There are a lot cryptography tools online. Some of good tool are made offline like OpenSSL.
Classic cipher / Simple decoder online tool
  1. 1.
    ​https://quipqiup.com - quipqiup is a fast and automated cryptogram solver
  2. 2.
    ​https://www.base64decode.org/ - base64 decoder
  3. 3.
    ​https://www.urldecoder.org/ - URL decoder
  4. 4.
    ​https://emn178.github.io/online-tools/base32_decode.html - Base32 decoder
  5. 5.
    ​https://cryptii.com/ - All in one tool
  6. 6.
    ​https://www.guballa.de/substitution-solver - Substitution solver
  7. 7.
    ​https://www.guballa.de/vigenere-solver - Vigenere solver
  8. 8.
    ​https://rot13.com/ - Rot 1 - 25 decryptor
  9. 9.
    ​https://www.dcode.fr - All in one tool
  10. 10.
    ​http://rumkin.com/tools/cipher/ - All in one tool
  11. 11.
    ​http://www.unit-conversion.info/texttools/morse-code/ - Morse code decoder
  12. 12.
    ​https://cryptii.com/pipes/ascii85-encoding - ASCII85 decoder
  13. 13.
    ​https://github.com/Ciphey/Ciphey -Ciphey
Modern cryptography
  1. 1.
    ​https://gchq.github.io/CyberChef/ - All in one tool
  2. 2.
    ​https://crackstation.net/ - Crack hash
  3. 3.
    Cryptool
  4. 4.
    John the Ripper
  5. 5.
    Hashcat
OpenSSL cheatsheet
  • Decrypt a file using RSA private key
    • openssl rsautl -decrypt -inkey pub_priv.key -in ciphertext.file -out decrypted.file
  • Decrypt a file using AES-256-CBC and a keyfile
    • openssl enc -d -aes-256-cbc -in ciphertext.file -out cleartext.file -pass file:./key.file
  • Decrypt a file using AES-256-CBC
    • openssl enc -aes-256-cbc -d -in file.txt.enc -out file.txt
  • Decrypt a file using AES-256-CBC with base64 encoded
    • openssl enc -aes-256-cbc -d -a -in file.txt.enc -out file.txt
  • Others reference
Cracking compressed file
  1. 1.
    John the Ripper - john --wordlist=/usr/share/wordlists/rockyou.txt hash.txt
  2. 2.
    fcrackzip - fcrackzip -D -u -p rockyou.txt filename.zip
​
Note: Sometimes there are some challenges that require you to develop your own decryptor for that particular challenge. Just make sure you have a good scripting/programming language to solve the challenges.
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Last modified 2mo ago