🌐 WebDecode
A detailed write-up of the Web challenge 'WebDecode' from PicoCTF - 2024
Contents
📊 Challenge Overview
Category Details Additional Info 🏆 Event PicoGym Event Link 🔰 Category Web 🌐 💎 Points Out of 500 total ⭐ Difficulty 🟢 Easy Personal Rating: 1/10 👤 Author Nana Ama Atombo-Sackey Profile 🎮 Solves 49.252 solve rate 📅 Date 28-01-2025 PicoGym 🦾 Solved By mH4ck3r0n3 Team:
📝 Challenge Information
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🎯 Challenge Files & Infrastructure
Provided Files
1
Files: None
🔍 Initial Analysis
First Steps
Initially, the website appears as follows:
By navigating the website through the navbar and visiting the
About
page, I obtained this:As the website itself suggested, I inspected the page using
ChromeDevTools
and found a strangeBase64
string:
🎯 Solution Path
Exploitation Steps
Initial setup
Once the Base64 string was found, the exploit was solely based on decoding it.
Exploitation
I decoded it directly using bash, with the
base64
command combined withecho
:
1
echo cGljb0NURnt3ZWJfc3VjYzNzc2Z1bGx5X2QzYzBkZWRfMTBmOTM3NmZ9 | base64 -d; echo "\n"
Flag capture
🛠️ Exploitation Process
Approach
The exploit makes a request to the page and uses bs4 to extract the flag in Base64, then decodes it and prints it.
🚩 Flag Capture
Flag
Proof of Execution
🔧 Tools Used
Tool Purpose Python Exploit
💡 Key Learnings
Skills Improved
- Binary Exploitation
- Reverse Engineering
- Web Exploitation
- Cryptography
- Forensics
- OSINT
- Miscellaneous
📊 Final Statistics
Metric | Value | Notes |
---|---|---|
Time to Solve | 00:00 | From start to flag |
Global Ranking | Challenge ranking | |
Points Earned | Team contribution |
Created: 28-01-2025 • Last Modified: 28-01-2025 *Author: mH4ck3r0n3 • Team: *