The bots were able to encrypt their secrets but we found that they were owned by bot3. Are there some traces of human-readable text?
The Linux challenges are consecutive, starting from part 1.
First, we must log in to bot4, using the previous flag as the password, and then change directory to bot4's home directory:
bot3@cybot01:~$ su bot4
Password:
bot4@cybot01:/home/bot3$ cd ~
Let's see what we have to work with:
bot4@cybot01:~$ ls -la
total 120
dr-xr-x--- 2 root bot4 4096 Jun 18 09:51 .
drwxr-xr-x 10 root root 4096 Jun 18 09:51 ..
lrwxrwxrwx 1 root root 9 Jun 18 09:51 .bash_history -> /dev/null
-r--r----- 1 bot4 bot4 220 Feb 25 2020 .bash_logout
-r--r----- 1 bot4 bot4 3771 Feb 25 2020 .bashrc
-r--r----- 1 bot4 bot4 807 Feb 25 2020 .profile
-r--r----- 1 bot4 root 99998 Jun 18 09:51 random-secrets
The flag must be in random-secrets!
bot4@cybot01:~$ strings random-secrets
Sahqueigh6Zahkoiqu
✂️--- SNIP ---✂️
However, the contents are filled with junk. To find the flag needle within this secrets haystack, we can use grep to search the strings:
bot4@cybot01:~$ strings random-secrets | grep CDDC
CDDC21{gRe3EpL1nG}
CDDC21{gRe3EpL1nG}