picoCTF 2018

The new version of picoCTF is live during end of September. After a strongly humbling experience in the last one (2017) I'm giving this one a shot.
https://2018game.picoctf.com/

Hideout

First 3 challenges are General Warmup, involving conversions:
- hex to decimal
- hex to ASCII
- decimal to binary

Resources

The flag is in plaintext on the webpage. (translates to "Thank you for coming here.")

Grep 1

An ASCII file with lots of text.
    grep pico ./file

net cat

Connect to the given system and port to get the flag.

Aca-Shell-A

Connect to the given service and follow along the prompts using your knowledge of Linux commands. They mainly involved echo, cd, ls, cp, whoami, rm.
This was one was a bit finicky as the copy command had to be run from the home folder and nowhere else.
picoCTF{CrUsHeD_It_9edaa84a}

Strings

Search for strings in the file and find the flag.
    strings ./file | grep pico
picoCTF{sTrIngS_sAVeS_Time_3f712a28}

pipe

Pipe the network output into a file
    nc 2018shell2.picoctf.com 44310 >> ./pipe1
    grep pico ./pipe1
picoCTF{almost_like_mario_a13e5b27}

grep 2

Use grep recursively in the folders:
    grep -R picoCTF ./*
picoCTF{grep_r_and_you_will_find_556620f7}

environ

Found as an environment variable:
    env
picoCTF{eNv1r0nM3nT_v4r14Bl3_fL4g_3758492}

ssh-keyz

Create a private-public keypair and add it to the server via the webshell:
   ssh-keygen -t rsa -C "<email>"
   
picoCTF{who_n33ds_p4ssw0rds_38dj21} 

what base is this

Convert the following:
    binary->ASCII
    hex->ASCII
   octal->ASCII
picoCTF{delusions_about_finding_values_3cc386de}

you can't see me

There is a folder named '.' which makes it tricky.
    grep -R pico ./.
picoCTF{j0hn_c3na_paparapaaaaaaa_paparapaaaaaa_22f627d9}