The Careless Spy

A spy working for a rival organization tried to send a secret flag back to his handler. He thought he was clever and used RSA to encrypt the message before sending it across the wire. Unfortunately for him, the spy generated his RSA keys on an old laptop with very limited entropy. The primes he used were small enough to be factored with today’s computers.

You’ve intercepted the following transmission:

n = 77790444096778209971153567921081374528904305407850142716915144438011550558357
e = 65537
c = 53546539636006495625883286312537258634547053357783792363817942364616639792976

Break the weak RSA, recover the plaintext, and uncover the flag the spy was trying to hide.


Flag Format: BUBT-CTF{******}