You can keep the first random number on the stack by sending and EOF. Using this, you can store it back with `xrelease`, passing the `xtest` check.

[https://github.com/x64x6a/ctf-writeups/tree/master/DEF_CON_CTF_Quals_2019/hotel_california](https://github.com/x64x6a/ctf-writeups/tree/master/DEF_CON_CTF_Quals_2019/hotel_california)

Original writeup (https://github.com/x64x6a/ctf-writeups/tree/master/DEF_CON_CTF_Quals_2019/hotel_california).