PicoCTF Writeup – Wave a flag
# Information:
CTF Name: PicoCTF
CTF Challenge: Wave a flag
Challenge Category: General Skills
Challenge Points: 10
picoCTF 2021.
# Used Tools:
- Linux
- file
- chmod +x
# Challenge Description:
Can you invoke help flags for a tool or binary? This program has extraordinarily helpful information…
Hints:
# Writeup:
Hello, and welcome to another picoCTF challenge write-up. First, I downloaded the program (that you can obtain under “Description”).
Step 1:
I used the command file to see what kind of data was stored in the program called: warm.
Has you can see in the image below.
As you can see in the image above, the file is executable, and if you insert de command ls -al, you will see what kind of permissions are being executed (as you can see in the image below).
If you have something like: rwxr-xr-x, it means that you can read, write and execute. In this case, we can do it all. We can read because we have an r, we can write because we have a w, and we can execute because we have an x.
If you want to better understand about Linux permissions take a look at this post.
Step 2:
After knowing that I had permission to execute, I used the ./ command to see what was in the current directory. As you can see in the image below.
I was prompted to enter an -h, and that is what I did.
I got the flag.
The flag is:
Thank you very much for reading!
Cheers,
SoBatista
