Nice netcat

Overview

Points: 15 Category: General

Description

There is a nice program that you can talk to by using this command in a shell: $ nc mercury.picoctf.net 43239, but it doesn't speak English...

Hints

1. You can practice using netcat with this picoGym problem: what's a netcat?
2. You can practice reading and writing ASCII with this picoGym problem: Let's Warm Up

Approach

First I connected to mercury.picoctf.net 43239 on a Linux terminal.

It gave these numbers:

112 105 99 111 67 84 70 123 103 48 48 100 95 107 49 116 116 121 33 95 110 49 99 51 95 107 49 116 116 121 33 95 55 99 48 56 50 49 102 53 125 10

These numbers are most likely ASCII values for text. I got tired of trying to look for an online source to decode it. I tried about 3 and they all didn't work. I wrote up a Python script

nums = [112, 105, 99, 111, 67, 84, 70, 123, 103, 48, 48, 100, 95, 107, 49, 116, 116, 121, 33, 95, 110, 49, 99, 51, 95, 107, 49, 116, 116, 121, 33, 95, 55, 99, 48, 56, 50, 49, 102, 53, 125, 10]
flag = ""
for number in nums:
    flag += chr(number)
print(flag)

Flag

picoCTF{g00d_k1tty!_n1c3_k1tty!_7c0821f5}