← Back to Writeups

Example Writeup

Author: Jordan Lanham
Event: Example CTF 2025
Category: Misc
Date: Jan 15, 2025
Read Time: 8 minutes

Overview

This is a template writeup showing how to format your CTF solution writeups. Replace this entire file with your actual writeup content.

Challenge Description

Provide a brief description of the challenge here. What was the objective? What were the constraints?

Example:

We were given a file called challenge.txt and needed to find the hidden flag using basic cryptography.

Initial Analysis

Start by describing what you found when you first examined the challenge:

  • What files or services were provided?
  • What were the initial observations?
  • What tools did you use for reconnaissance?

Solution Approach

Walk through your step-by-step approach to solving the challenge:

Step 1: Reconnaissance

Describe your initial exploration of the challenge. What did you discover?

Step 2: Vulnerability Identification

What vulnerability or weakness did you find?

Step 3: Exploitation

How did you exploit the vulnerability? What was your attack strategy?

Step 4: Flag Extraction

How did you get the final flag?

Code / Exploit

Include your solution code here:

#!/usr/bin/env python3
# Example solution code

def solve_challenge(input_file):
    with open(input_file, 'r') as f:
        data = f.read()
    
    # Your solution logic here
    return flag

if __name__ == "__main__":
    flag = solve_challenge("challenge.txt")
    print(f"Flag: {flag}")

Or in another language:

#!/bin/bash
# Bash solution example

echo "Processing challenge..."
flag=$(cat challenge.txt | tr 'a-z' 'n-za-m')  # ROT13 example
echo "Flag: $flag"

Technical Details

Explain any important technical concepts or tricks used:

  • Encryption/Decryption: What algorithm was used?
  • Encoding: Base64, hex, ASCII?
  • Protocol: HTTP, SSH, custom?
  • Vulnerability: SQL injection, XSS, buffer overflow?

Key Insights

What did you learn from this challenge? What techniques could be reused?

  • This type of challenge teaches you about [X concept]
  • A useful tool to remember is [Y tool]
  • Watch out for [Z common mistake]

The Flag

flag{this_is_the_example_flag_format}

Resources

Links to helpful resources used in solving this challenge:

Tips for writing great writeups:

  • Be clear and verbose - assume the reader hasn't seen the challenge
  • Include code snippets and command examples
  • Explain the "why" not just the "what"
  • Use headers and formatting to organize your thoughts