Aperi’CTF 2019 - Aperi’Bot - Welcome

Challenge details

Event	Challenge	Category	Points	Solves
Aperi’CTF 2019	Aperi’Bot - Welcome	MISC	50	26

Aperi’Bot is the welcome challenge of the Aperi’CTF event. It has been built to provide a simple test for Internet access, ensure that all teams are familiar with the platform and be fun 😊

Task description:

Welcome to the Aperi’CTF!

Check out Telegram and play with our @APRK_bot bot.

To authenticate yourself, send this command to the bot:

/auth zjny65fbxBmz2Q4G9e4vBQKT5fWuTnSUbW9PPgKa6hTuzpVPzjUa7FvsN5VAkMey

Note: If you don’t have a Telegram account and don’t want to create one, you can ask the staff for the flag.

Let the challenge begin!

Telegram bot

First, we need to checkout the APRK_bot using our Telegram account:

Let’s start a new conversation with the bot:

We’re given a set of command list that we can use to interact with the bot, let’s send ❤ to Aperi’Kube!

Okay, the bot seems to work properly, we should now be able to authenticate and get the flag!

The bot wants to play a game, let’s play!

THE GAME

The game that the bot wants to play with us is the Rock, Paper, Scissors, Lizard, Spock which is a variant of the famous Rock, Paper, Scissors with the following rule:

• Scissors cuts Paper
• Paper covers Rock
• Rock crushes Lizard
• Lizard poisons Spock
• Spock smashes Scissors
• Scissors decapitates Lizard
• Lizard eats Paper
• Paper disproves Spock
• Spock vaporizes Rock
• Rock crushes Scissors

After several attempts to beat the bot, we finally get the flag:

The final flag is APRK{W3lc0m3_t0_Ap3r1_CTF!!}

Happy Hacking!

Creased