Exploit-Exercises : Nebula

Here I give hints to solving various levels of the Exploit Excercises Nebula,. 

Level00

non-required

Level01
symbolic links, override echo

Level02
env variables

Level03
Cron does not output to stdout.


Level04
Symbolic links


Level05
.backup, tar -xvzf <filename>. ssh key-pair


Level06
/etc/passwd


Level07
webserver, url escaping, input sanitization

Level08
tcpdump,


Level09
system()


Level10
https://en.wikipedia.org/wiki/Time_of_check_to_time_of_use#Examples
nc -kl 18211

Level11


PS.  You can find many sources for full solutions. This is just to help yourselves when stuck and yet think about it yourselves.