Intended solution

tl;dr Coppersmith's Theorem + CRT

Full writeup: [https://masterpessimistaa.wordpress.com/2018/10/11/inctf-2018-crypto-writeups-part-1/](https://masterpessimistaa.wordpress.com/2018/10/11/inctf-2018-crypto-writeups-part-1/)

Original writeup (https://masterpessimistaa.wordpress.com/2018/10/11/inctf-2018-crypto-writeups-part-1).