One Part!

RSA-CRT. We're given dp, which is d modulus p - 1. This is the exact same problem as Weirder RSA from picoCTF 2017, so I shamelessly copied the script and changed the parameters, revealing the flag

https://hgarrereyn.gitbooks.io/th3g3ntl3man-ctf-writeups/content/2017/picoCTF_2017/problems/cryptography/weirderRSA/weirderRSA.html

Flag: FwordCTF{i_knew_it_its_not_secure_as_i_thought}