So, here we are after playing a very fun ctf. My team ended up at no. 49 with 3140 points. Here are the writeups for some challenges. 1. Tyrannosaurus Rex Description: We found this fossil. Can you reverse time and bring this back to life? In the python script, we can see that…

CTFlearn writeups for some beginner challenge — 1. The Credit Card Fraudster I just arrested someone who is probably the most wanted credit card fraudster in Europe. She is a smart cybercriminal, always a step ahead INTERPOL and she kept unnoticed for years by never buying online, but buying goods with a different card every time and in different stores. My cyber-analysts…

This was a beginner-intermediate level ctf. Many challs were easy, some were guessy and some were fun. My team ended up at no-49 with 12805 points. 1. little-RSA This challenge had a file attached to it with these values: c=32949 n=64741 e=42667 `n`was easily factorable: 641*101, which resulted in totient=64000. Second step…

By: Aviral Gupta 1. base646464: The ciphertext was multiple b64 encodings. Script for decoding: f=open("cipher.txt").read() while(True): try: f=f.decode('base64') except: print f break #flag{l00ks_l1ke_a_l0t_of_64s} 2. Psuedo-key: In this chall, key and the plaintext are encoded with the same function i.e. encrypt. To get plaintext, first we have to recover key. We know that each character…