Tags: factoring pollard-p-1 crypto totient-function rsa

Rating: 5.0

TL;DR: recover prime factors of λ(n) from r_j = prod(s_i) + 1 where s_i are factors of the period. Then use d = e^{-1} mod(prod(r_j)) as decryption exponent, since (hopefully) prod(r_j) = k * λ(n)

Full writeup and analysis at <https://ur4ndom.dev/posts/2022-07-04-gctf-cycling/>

Original writeup (https://ur4ndom.dev/posts/2022-07-04-gctf-cycling/).