HackTheBox Sekure Decrypt Challenge

Explore the basics of cybersecurity in the Sekure Decrypt Challenge on Hack The Box. This easy-level Challenge introduces encryption reversal and file handling concepts in a clear and accessible way, perfect for beginners.

https://app.hackthebox.com/challenges/213

Description

Timmy created a secure decryption program

Exploitation

binwalk -eM core

#!/usr/bin/env python3
from Crypto.Cipher import AES

def decrypt_flag():
    key = b'VXISlqY>Ve6D<{#F'
    iv = b'AAAAAAAAAAAAAAAA'
    ciphertext = bytes.fromhex('322608dbef900b1ebcd3a058719148830000000000000000')[:16] 
    cipher = AES.new(key, AES.MODE_CBC, iv)
    plaintext = cipher.decrypt(ciphertext)
    print(f"Key: {key.decode()}")
    print(f"IV: {iv.decode()}")
    print(f"Flag: {plaintext.decode()}")

if __name__ == "__main__":
    decrypt_flag()

Summary

The Sekure Decrypt Challenge on Hack The Box is an easy-level reverse engineering puzzle that introduces AES decryption and binary analysis. Participants extract an encrypted payload from a binary file and decrypt it using a fixed AES key and IV. By leveraging tools like binwalk and the Crypto library, the challenge demonstrates how to reverse-engineer encrypted data and uncover hidden messages. Ideal for beginners, it provides hands-on experience with binary forensics and cryptographic analysis, offering a practical introduction to encryption reversal and data extraction.