Hi All - another Professor Bill Buchanan contribution:
With RSA, we create two random prime numbers (p and q), and determine the modulus (N=pq). We encrypt a message with C=M^e (modN) and decrypt with M=C^d (modN), and where (e,N) is the encryption key and (d,N) is the decryption key.
We can crack RSA with Chinese Remainder Theory (CRT), and where we create three ciphers with the same message and three different encryption keys. We will use CRT and logarithms to determine the original message. In this case, we will generate a challenge which has the same message, ciphered with three different modulus values (N=p.q). The method we will outline is also known as the Håstad broadcast attack.
https://asecuritysite.com/cracking/rsa_ctf01
Note the site may have a check you are human verification these days.
Regards
Caute_Cautim
