Hack The Box CTF Writeup Template

This repository contains a template/example for my Hack The Box writeups. Below you'll find some information on the required tools and general work flow for generating the writeups. I also write about it on my blog here, which has some details about also posting the markdown on Jekyll.

Installation on Arch Linux

1. Install Latex and support packages for Latex via sudo pacman -S texlive-most.
2. Install Pandoc via sudo pacman -S pandoc bcprov java-commons-lang .
3. Install PDFtk via sudo pacman -S pdftk.
4. Install the Pandoc Latex Template
   • Download the latest version of the Eisvogel template from the release page.
   • Extract the tar.gz archive and open the folder.
   • Create a pandoc templates folder if it doesn't exist at ~/.pandoc/templates/.
   • Move the template eisvogel.tex to your pandoc templates folder and rename the file to eisvogel.latex.

Installation on Ubuntu 18.04 LTS

Note: If you use Debian or Mint it may work but your mileage here might vary.

1. Install Latex via sudo apt-get install texlive.
2. Install extra support packages for Latex sudo apt install texlive-xetex.
3. Install extended fonts for Latex sudo apt-get install texlive-fonts-recommended texlive-fonts-extra.
4. Install Pandoc via sudo apt-get install pandoc.
5. Install the Pandoc Latex Template
   • Download the latest version of the Eisvogel template from the release page.
   • Extract the tar.gz archive and open the folder.
   • Create a pandoc templates folder if it doesn't exist at ~/.pandoc/templates/.
   • Move the template eisvogel.tex to your pandoc templates folder and rename the file to eisvogel.latex.
6. Make sure you have PDFtk installed via sudo snap install pdftk.

Usage

Initially I publish my writeups as a password protected pdf, the password set to the root flag for the box. After the box is retired, I post the writeup on my Jekyll site.

Here's the directory structure for my writeup template.

HTB_Writeup-TEMPLATE
│   HTB_Writeup-TEMPLATE-d0n601.md   
│
└───pdf
│   │   HTB_Writeup-TEMPLATE-d0n601.pdf
│   │
│   └───protected
│       │   HTB_Writeup-TEMPLATE-d0n601.pdf
│   
└───images
│       │   bg.pdf
│       │   someotherimage.png
│       │   ...

Markdown for pdf

In order to generate a pdf from markdown using pandoc we must format the header correctly. The header for my template is as follows.

---
title: "Hack The Box - BOX NAME HERE"
author: Ryan Kozak
date: "2021-06-15"
subject: "CTF Writeup Template"
keywords: [HTB, CTF, Hack The Box, Security]
lang: "en"
titlepage: true
title-page-color: "141d2b"
titlepage-rule-color: "11b925"
titlepage-text-color: "FFFFFF"
toc: true
toc-own-page: true
titlepage-background: "./images/bg.pdf"
...

Once the writeup is complete, or you're just looking to build it to see how it's looking as a pdf, issue the following command from your writeup directory.

Arch Linux

pandoc --pdf-engine=xelatex ./HTB_Writeup-TEMPLATE-d0n601.md -o ./pdf/HTB_Writeup-TEMPLATE-d0n601.pdf --from markdown --template eisvogel --listings

Ubuntu 18.04

pandoc --latex-engine=xelatex ./HTB_Writeup-TEMPLATE-d0n601.md -o ./pdf/HTB_Writeup-TEMPLATE-d0n601.pdf --from markdown --template eisvogel --listings

Password Protect pdf

Update: Now, HTB has dyamic flags, so while this is a nice tutorial on how to password protect a PDF, it doesn't really make sense any more to use your root flag as the password. No one else will have the same root flag as you, so only you'll know how to get in. Some folks are using things like the /etc/shadow file's root hash.

To password protect the pdf I use pdftk. From the root folder of the writup directory issue the following command.

pdftk ./pdf/HTB_Writeup-TEMPLATE-d0n601.pdf output ./pdf/protected/HTB_Writeup-TEMPLATE-d0n601.pdf user_pw v5gw5zkh8rr3vmye7p4ka

Now a password protected pdf will appear in the /pdf/protected directory.