decryptStuff

CTF Decryption Toolkit

Overview

The CTF Decryption Toolkit is a collection of tools and scripts designed to assist with decryption challenges commonly encountered in Capture The Flag (CTF) competitions. It supports various encryption algorithms, file formats, and encoded data types, enabling users to quickly analyze and decrypt data to solve challenges efficiently.

Goal for repo features

Support for Common Encryption Algorithms:

• AES (128, 192, 256)
• DES, 3DES
• RSA
• XOR-based encryption
• Encoding Decoders:
• Base64, Base58, Base32
• Hexadecimal and Binary
• URL Encoding
• File Type Analysis:
• Extract metadata from files (e.g., exiftool)
• Identify file types (binwalk, file)
• Steganography Tools:
• Hidden data extraction from images and files.
• Brute-forcing Tools:
• Automated brute-force for simple ciphers and passwords.
• Modular and Extensible:
• Add custom scripts and algorithms as needed.

Getting Started:

• Installation -- Clone the repository:

bash

git clone https://github.com/username/ctf-decryption-toolkit.git cd ctf-decryption-toolkit

Dependencies

Install the required Python libraries:

bash

pip install -r requirements.txt

Additional tools somewhat required:

OpenSSL binwalk steghide exiftool

Install them on Linux-based systems:

bash

sudo apt-get install openssl binwalk steghide libimage-exiftool-perl Usage Decrypting AES Files Decrypt AES-encrypted files using the provided script:

bash

python tools/aes_decrypt.py --file encrypted_file.enc --key YOUR_KEY --iv YOUR_IV Decoding Base64 Strings Decode a Base64 string:

bash

python tools/base64_decode.py --data "SGVsbG8gV29ybGQ=" Extracting Hidden Data Use binwalk to extract hidden files:

bash

binwalk -e suspicious_file.img Steganography Extract hidden messages from image files:

bash

steghide extract -sf hidden_image.jpg Tool List Python Scripts aes_decrypt.py - AES decryption with custom key and IV. xor_crack.py - Crack XOR-encrypted text or files. rsa_decrypt.py - RSA decryption with private key. base64_decode.py - Decode Base64-encoded strings.

External Tools

openssl - Encryption and decryption for various algorithms. binwalk - Analyze and extract data from binary files. steghide - Extract hidden data in image/audio files. exiftool - Analyze metadata in files.

Contributing - We welcome contributions! If you have a tool or script to add, follow these steps:

Fork the repository. Create a branch for your feature. Add your tool to the appropriate directory (e.g., tools/). Update README.md with usage instructions. Submit a pull request.

Feel free to adapt this README to suit your repository's structure and focus!