Json Tree Reverse Engineering

from http://ctf.cyberspecters.com
chall name :

JSON S13

13 solved

Given the json source file :

chall.json

We can identify the flas is in that json file because we can search SPEC and we found

Pasted image 20240216042733.png

BUT is randomized the position so we cant know exactly the next flag is. but i found the suspicious name , there is "identifierName": "str1"
we know if SPEC is the first letter on the flag. and for the next flag i want search str2 and we found.
Pasted image 20240216042831.png
TERS
SPECTERS

okkk, next string str3. and continued untill str13

SPECTERS{rU5

untill str13 and we got
SPECTERS{rU5L4n5a5m1T45AyUrManToB4mb4Ng5am5uD1n}

Flag submitted...