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RingZero CTF - Forensics - I Love cat

RingZero CTF - Forensics - I Love cat


Objective:
I love cat! Do you?

User: cat
Password: cat
ssh challenges.ringzer0team.com port 10252

Solution:


So let's start up and SSH to challenges.ringzer0team.com on port 10252

Login as            cat
pass                  cat


Lets start by seeing what is in our directory

cat@lxc-forensics-252:~$ ls
commands  flag.txt


is it as easy as just catting the flag.txt file?

cat@lxc-forensics-252:~$ cat flag.txt
**************************** WHERE IS THE FLAG ? ****************************


Nope lets see what else is in the directory

cat@lxc-forensics-252:~$ ls -al
total 20
drwxr-xr-x 3 root root 4096 Jul 17 18:36 .
drwxr-xr-x 3 root root 4096 Jul 17 18:23 ..
-rw-r--r-- 1 root root  221 Jul 17 18:30 .bash_profile
drwxr-xr-x 2 cat  cat  4096 Jul 17 18:25 commands
-rw-r--r-- 1 root root  116 Jul 17 18:36 flag.txt

a directory name commands

cat@lxc-forensics-252:~$ cd commands/
-rbash: cd: restricted

lets try to ls the directoy
cat@lxc-forensics-252:~$ ls ./commands/
cat  ls


ok we only can use cat and LS

let's check out  the cat man to see if we might get some help there


CAT(1)                          User Commands                         CAT(1)

NAME         top

       cat - concatenate files and print on the standard output

SYNOPSIS         top

       cat [OPTION]... [FILE]...

DESCRIPTION         top

       Concatenate FILE(s) to standard output.

       With no FILE, or when FILE is -, read standard input.

       -A, --show-all
              equivalent to -vET




CAT(1)                          User Commands                         CAT(1)




NAME         top


       cat - concatenate files and print on the standard output




SYNOPSIS         top


       cat [OPTION]... [FILE]...




DESCRIPTION         top


       Concatenate FILE(s) to standard output.

       With no FILE, or when FILE is -, read standard input.

       -A, --show-all
              equivalent to -vET






That -A looks interesting 






Let's try cat with -A on flag.txt










cat@lxc-forensics-252:~$ cat -A flag.txt
FLAG-0K14eDrm4t5g7KD54X8Dl3NNcZ956oCK^M**************************** WHERE IS THE FLAG ? ****************************$











Bam we got the flag






FLAG-0K14eDrm4t5g7KD54X8Dl3NNcZ956oCK




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