Rating:

Flag is stored on qwords above the two uninitialized bits of data it's trying to compare - easily visible in IDA.

https://advancedpersistentjest.com/2018/02/24/writeup-flag-checker-2-mario-mystery-envy-xiomara-ctf/

Original writeup (https://advancedpersistentjest.com/2018/02/24/writeup-flag-checker-2-mario-mystery-envy-xiomara-ctf/).