From NixNet

This is the game they recommend beginners starting with. Some of the levels were easy but some were much more challenging.

Accessing Level 0

SSHing into a machine

ssh -p 2220

Level 0

Displaying the contents of a file

cat readme

Level 1

Dealing with programs that take - as an option to read from stdin and files named -: give the path to the file

cat ./-

Level 2

Spaces in file names - escape with with \, use single/double quotes around the full name, or use Tab

cat spaces\ in\ this\ filename

Level 3

Display hidden file

ls -a inhere
cat inhere/.whateverthenamewas

Level 4

There's a better way to do this but I just displayed the contents of each file until I found the one with the password.

cat inhere/*

Level 5

Find a file with specific attributes

find \! -executable -size 1033c -exec ls {}\;

Level 6

Same as previous

find -size 33c -user bandit7 -group bandit6

Level 7

Search for a string on the same line as another string

There's a better way to do this but I didn't bother figuring it out. This works ¯\_(ツ)_/¯

cat data.txt | grep millionth

Level 8

Find a single unique line in a massive text file

sort data.txt | uniq -u

uniq only looks for unique lines that are adjacent to one another; sort will put duplicate lines next to each other so uniq can filter them out.

Level 9

Print readable characters in a file and search through them for a string

strings data.txt | grep ==

Level 10

Password: truKLdjsbJ5g7yyJ2X2R0o3a5HQJFuLk