imgFigure 1 - Hack the Box Website


Introduction

Hack The Box or HTB is one of the most popular CTF websites. This article will walk you through how to sign up for HTB tell you about Rule #7.

Here are some of the reasons to join HTB:

imgFigure 2 - Reasons to join Hack The Box

HTB has two membership models:

  1. Free and
  2. VIP (10 Euro/mo).

Figure 3 shows the differences between these two models.

imgFigure 3 - Free vs VIP membership models for HTB

The website has a join link that mentions an ‘Invite Challenge’, as shown in Figure 4.

imgFigure 4 - Join button with a hint to an ‘Invite Challenge’.

Instructions

This section documents the steps to sign up for HTB by solving the ‘Invite Challenge’.

Required Tools

This section has been removed due to Rule #7.

‘Join’ Button

Most section has been removed due to Rule #7.

The ‘Join’ button in Figure 4 directs users to https://www.hackthebox.eu/invite. Figure 5 shows the invite web page. The title of this web page contains the text ‘Can you hack this box?’. This confirms that a challenge needs to be solved to join the website.

imgFigure 5 - Invite Web page.

Code Analysis

Most of this section has been removed due to Rule #7.

The following lesson could be derived from the code analysis:

If an observer doesn’t understand the message, then encode it differently.

Generating the invite

This section has been removed due to Rule #7.

Signing Up for HTB

The key from the last section was used to Sign up for HTB as shown in Figure 6.

imgFigure 6 - Congratulations!

Summary

After writing this post and signing up I was greeted with the rules. Reviewing the rules, one rule pops out. Rule #7 mentions not sharing the generation technique of the invite code, as shown in Figure 7.

imgFigure 7 - Dont spoil!

Due to this rule, I’ve decided to remove most of this article.

imgKeep Calm and Hack This Box (and Dont spoil)