PicoCTF Writeup – Python Wrangling
# Information:
CTF Name: PicoCTF
CTF Challenge: Python Wrangling
Challenge Category: General Skills
Challenge Points: 10
picoCTF 2021.
# Used Tools:
- Linux
- cat
- python3
# Challenge Description:
Python scripts are invoked kind of like programs in the Terminal… Can you run this Python script using this password to get the flag?
Hints:
# Writeup:
Hello, and welcome to another picoCTF challenge write-up. First, I downloaded the python script, the password, and the flag files.
Step 1:
I used the command cat to find out what was in the Python script, and I was presented with the following code:
Step 2:
I read the code that was in the file ende.py, and I noticed that there was information on how to decrypt a file (which is what we intend to do with the file “flag.txt.en”, where the “en” in the file means encrypted).
We can see this in the image below.
Step 3:
I replaced “python “+ sys.argv[0] +” -d pole.txt” with the correct information. In the following way:
As you can see, I replaced “python” with “python3” because python3 is the one that I use. And I put python3 because it will read the python program that is in front of it, which in this case is “ende.py”.
In front of “ende.py” I added the file that I want to decrypt, wich is “flag.txt.en”.
And this together will stay as we can see in the image above.
Step 4:
Afterwords, I was able to get the password using the cat command on the file “pw.txt”.
Then, I entered the following command: “python3 ende.py – d flag.txt.en”, and I was prompted to insert the password stored in “pw.txt” file, as you can see in the image below.
I got the flag.
The flag:
Thank you very much for reading!
Cheers,
SoBatista