XOR Cryptography with Python | TryHackMe W1seGuy
We solved a cryptography CTF challenge where XOR encryption and HEX encoding were used to encrypt and encode the challenge flag. We used Python to craft an XOR decryption statement to decrypt the first four characters of the flag, THM{, in order to find the decryption key. This was part of TryHackMe W1seGuy room.
Task Scenario
Yes, it’s me again with another crypto challenge!
Have a look at the source code before moving on to Task 2. You can review the source code by clicking on the Download Task Files button at the top of this task to download the required file.
Your friend told me you were wise, but I don’t believe them. Can you prove me wrong?
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Understanding the python source code
Source code is below:
In the source code above, The function will first generate a random key of length as shown below:
And below is the call to the function setup
The function takes the encryption key and uses encryption on the first flag by iterating over all characters of the flag and ‘ing it with .
Lastly it applies encoding on the result:
The lin below prints the encrypted and encoded flag returned from the function.
Afterwards, it asks for the encryption key and reads the user input. If the or the input provided matches the randomly generated, the code the prints the second flag read from .
Check out the video below for detailed explanation.
Room Answers | TryHackMe W1seGuy
Room answers can be found here.