📄️ Cycling - GoogleCTF 2022
It is well known that any RSA encryption can be undone by just encrypting the ciphertext over and over again. If the RSA modulus has been chosen badly then the number of encryptions necessary to undo an encryption is small. However, if the modulus is well chosen then a cycle attack can take much longer. This property can be used for a timed release of a message. We have confirmed that it takes a whopping 2^1025-3 encryptions to decrypt the flag. Pack out your quantum computer and perform 2^1025-3 encryptions to solve this challenge. Good luck doing this in 48h.
📄️ Least Common Genominator - GoogleCTF 2023
Someone used this program to send me an encrypted message but I can't read it! It uses something called an LCG, do you know what it is? I dumped the first six consecutive values generated from it but what do I do with it?!