**G**reetings, fellow cybersecurity enthusiasts and CTF players! In this writeup, we will dive into the solution of the “mini_RSA” challenge from the BackdoorCTF 2023.

**Challenge Overview:**

Groot has encrypted a message using RSA with a key size of 512 bits and a public exponent (RSA_E) of 3. The challenge provides two files: script.py and output.txt. The former contains the RSA encryption script used by Groot, while the latter presents the output ciphertext (c) and the modulus (n).

Let’s explore the provided files and understand the challenge before revealing the solution.

Writeup by [@sakibulalikhan](https://www.linkedin.com/in/sakibulalikhan/), read more on **Medium**: [https://sakibulalikhan.medium.com/backdoorctf-2023-mini-rsa-challenge-writeup-937984bd1e58](https://sakibulalikhan.medium.com/backdoorctf-2023-mini-rsa-challenge-writeup-937984bd1e58)

Original writeup (https://sakibulalikhan.medium.com/backdoorctf-2023-mini-rsa-challenge-writeup-937984bd1e58).