Modern & Applied Cryptography Breakers Advanced
Breaking Toy ECC with Pohlig-Hellman
Elliptic curve security does not come from the size of the field. It comes from one number: the largest prime factor of the group order. When that order is smooth, Pohlig-Hellman splits the discrete log into tiny subgroups and solves it in a flash. This guide runs the real attack on a toy curve and recovers the private key.
13 min read