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HackTheBox Ouija Challenge

Explore the basics of cybersecurity in the Ouija 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/410

Description

You’ve made contact with a spirit from beyond the grave! Unfortunately, they speak in an ancient tongue of flags, so you can’t understand a word. You’ve enlisted a medium who can translate it, but they like to take their time…

Exploitation

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#!/usr/bin/env python3

def decrypt():
    encrypted = "ZLT{Kdwhafy_ak_fgl_gtxmkuslagf}"
    key = 18
    decrypted = ""
    for c in encrypted:
        if c.islower():
            if ord(c) - key <= 96:
                c = chr(ord(c) + 26)
            dec = chr(ord(c) - key)
            decrypted += dec
        elif c.isupper():
            if ord(c) - key <= 64:
                c = chr(ord(c) + 26)
            dec = chr(ord(c) - key)
            decrypted += dec
        else:
            decrypted += c     
    return decrypted

print("Flag:", decrypt())

Summary

The Ouija Challenge on Hack The Box is an easy-level cryptographic puzzle that introduces participants to the basics of encryption reversal using a Caesar cipher. The challenge involves decrypting a message encoded in an “ancient tongue of flags” by applying a fixed shift value to reverse the encryption process. By writing a simple Python script to handle both uppercase and lowercase letters, participants can uncover the hidden flag. This challenge serves as an excellent introduction to fundamental cryptographic concepts, such as symmetric key encryption and character manipulation, making it ideal for beginners in cybersecurity. It provides a practical and accessible way to understand basic encryption schemes and their reversal techniques.

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