[xor]

21 ) Supercow - 40
Daedalus Corp. has a special utility for printing .cow files at /home/daedalus/supercow. Can you figure out how to get it to print out the flag?


The supercow application executes with the permissions of who created it, not who is running it.
It also only allows the reading of files which have a .cow extension

What we need to do is make a symbolic link between the flag.txt and {anything}.cow

The only problem is we need a directory we can write to.
Luckily we have /tmp/ which has write but no read permissions (to stop you from leeching other peoples solutions..)

So we can run a few commands to get our flags

Code:

mkdir /tmp/thebytecodeclub
ln -s /home/daedalus/flag.txt /tmp/thebytecodeclub/flag.cow
/home/daedalus/supercow /tmp/thebytecodeclub/flag.cow

Which will output
___________________________
< cows_drive_mooooving_vans >
---------------------------
\ ^__^
\ (oo)\_______
(__)\ )\/\
||----w |
|| ||

Giving us another flag :D


22 ) Write Right - 50
Can you change the secret? The binary can be found at /home/write_right/ on the shell server. The source can be found here.




If you wish to work on the harder problems with me, I will be on the IRC channel while solving them