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Pico CTF - runme.py

· One min read
Marios Daskalas
Cyber Security Specialist

This challenge is extremely easy. You use wget to download the file and then run the script using Python.

If you want to learn more about wget, then in the terminal type the following.

man wget
wget https://artifacts.picoctf.net/c/34/runme.py

A short description from Wikipedia: GNU Wget (or just Wget, formerly Geturl, also written as its package name, wget) is a computer program that retrieves content from web servers. It is part of the GNU Project. Its name derives from "World Wide Web" and "get". It supports downloading via HTTP, HTTPS, and FTP.

python3 runme.py

That's all.

Pico CTF - Mind your Ps and Qs

· One min read
Marios Daskalas
Cyber Security Specialist

First, download the file and use the following command to see it's contents.

cat values

That in turn, returns the following output.

Decrypt my super sick RSA:
c: 8533139361076999596208540806559574687666062896040360148742851107661304651861689
n: 769457290801263793712740792519696786147248001937382943813345728685422050738403253
e: 65537

Pico CTF - Mod 26

· One min read
Marios Daskalas
Cyber Security Specialist

We are being presented with the following description "Cryptography can be easy, do you know what ROT13 is?" and the following text.

cvpbPGS[arkg_gvzr_V'yy_gel_2_ebhaqf_bs_ebg13_Ncualgvd]

This is a cipher text, meaning that the letters of the alphabet need to be 'moved' 13 places forward, in order to decrypt the message.

Pico CTF - PW Crack 5

· 2 min read
Marios Daskalas
Cyber Security Specialist

First, download all the files provided. They are the following. All of them are needed to live in the same directory in order for this to work.

level5.py
level5.flag.txt.enc
level5.hash.bin
dictionary.txt

Now let's open up the main file which is the level5.py

Pico CTF - PW Crack 4

· 3 min read
Marios Daskalas
Cyber Security Specialist

First, download all the files provided. They are the following. All of them are needed to live in the same directory in order for this to work.

level4.py
level4.flag.txt.enc
level4.hash.bin

Now let's open up the main file which is the level4.py

Pico CTF - PW Crack 3

· 3 min read
Marios Daskalas
Cyber Security Specialist

First, download all the files provided. They are the following. All of them are needed to live in the same directory in order for this to work.

level3.py
level3.flag.txt.enc
level3.hash.bin

Now let's open up the main file which is the level3.py

Pico CTF - PW Crack 2

· 2 min read
Marios Daskalas
Cyber Security Specialist

First, download both the files and store them in the same directory.level2.py and level2.flag.txt.enc

Then use the following command in the terminal to see the contents of the file.

nano level2.py

Pico CTF - PW Crack 1

· One min read
Marios Daskalas
Cyber Security Specialist

First, dowload both the files in store them in the same directory. (level1.py and level1.flag.txt.enc).

Open up the level1.py using your favorite editor or with the following command from the terminal.

nano level1.py
### THIS FUNCTION WILL NOT HELP YOU FIND THE FLAG --LT ########################
def str_xor(secret, key):
#extend key to secret length
new_key = key
i = 0
while len(new_key) < len(secret):
new_key = new_key + key[i]
i = (i + 1) % len(key)
return "".join([chr(ord(secret_c) ^ ord(new_key_c)) for (secret_c,new_key_c) in zip(secret,new_key)])
###############################################################################

flag_enc = open('level1.flag.txt.enc', 'rb').read()

def level_1_pw_check():
user_pw = input("Please enter correct password for flag: ")
if( user_pw == "1e1a"):
print("Welcome back... your flag, user:")
decryption = str_xor(flag_enc.decode(), user_pw)
print(decryption)
return
print("That password is incorrect")

level_1_pw_check()

Pico CTF - Permissions

· One min read
Marios Daskalas
Cyber Security Specialist

First, click on the button 'Launch Instance'. Then ssh to the remote machine using the presented command. Yours might be with different port or user credentials.

ssh -p 50477 picoplayer@saturn.picoctf.net

Then navigate to the following folder using CLI.

cd /challenge/
cat metadata.json

That's all!