PwC Write up North Korea

Đề:
The most useful testing IQ page ever was released! Check your brain!
http://128.199.89.195:8002/


Bài này khá là troll :v mình đã chơi thử đến level 11, thì gặp câu BILL GATE có bao nhiêu tiền :v quỳ sấp mặt, và được đàn anh khen là Low IQ ever :v

Ok nên mình đã bình tĩnh lại và nhận ra rằng mỗi lần ta chơi thua, ta đều bị quay lại từ đầu cơ mà khi nhấp back thì ta lại quay chính vòng chơi trước
http://128.199.89.195:8002/index.php?level=865c0c0b4ab0e063e5caa3387c1a8741
Ok vậy là bây giờ có thể ta chỉ cần điền đúng đối số cho level, ta có thể qua màn 1 cách dễ dàng
mình thử check xem level có theo quy luật nào k thì thấy rằng đối số truyền vào level là 1 số đã bị md5 encode


Mình thử decode và thấy rằng nó chính là md(i)




theo La mã thì
i = 1
ii = 2
iii = 3
.....
ở vòng mình kẹt là vòng 11 vậy nên sẽ là xi
ở vòng 11 mình được thông báo là đã đang close to the flag -> mình thử vào level = md5(xiii)


Ok thấy gái xinh là phải Of course chứ gì nữa
















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