d:CTF 2023

The CTF competition arranged for the d:hack 2023 hackathon at DIPS AS.

Challenges designed by @raymonshansen, @olivernilssen, @orjanj and @jaalu.

Setup

If you have Docker Compose installed, you can run the challenges yourself by cloning the project and running docker-compose up in the root directory.

Note that Next Generation Calculator is commented out as it is very resource-intensive.

Challenge types

Challenges are divided into five categories:

• Crypto: challenges about cryptography and code breaking
• Investigation: challenges about reverse-engineering secrets and data from files and programs
  • This category covers both reverse-engineering and forensics categories in other CTFs
• Pwn: challenges about discovering and exploiting vulnerabilities
• Misc: challenges about creative problem solving
• Web: challenges about exploiting vulnerabilities in web applications

Useful tools

Windows utilities

• Windows Sandbox lets you set up disposable Windows environments quickly - nice if you only need a tool for a specific challenge!
• Windows Subsystem for Linux lets you set up a Linux environment as part of your Windows installation.

Programming

• If you're new to programming, Python is a nice scripting language with lots of resources available.
  • Automate the Boring Stuff is a good practical guide to Python
• Some challenges may require the .NET SDK

Cryptography

• CyberChef - a Swiss army knife of cryptography, which offers encryption, decryption and general file analysis tools
• DCode - handy utilities for analyzing and breaking classical ciphers

Investigation/Reverse engineering

• GHIDRA - a full software reverse engineering suite, offering disassembly, decompilation, and graphing
• IDA Free - the free version of the established reverse-engineering and debugging toolkit, also offers a decompiler
• dnSpy - .NET assembly decompiler and editor
• dotPeek - JetBrains' .NET decompiler
• Binwalk - file analysis tool

Web

• The browser developer tools -- accessible with the shortcut F12 in Firefox and Chromium-based browsers
• Postman - lets you craft your own HTTP requests to web apps
• Fiddler - lets you observe traffic to and from your computer

Pwn

• Burp Suite - toolkit to map and exploit vulnerabilities in web applications
• Pwntools - a Python library with utilities for networking, exploit development and common CTF tasks