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2 September 2020 write-up: old-14

Link point tag
old-14 100 JavaScript

Welcome back to another CTF writeup. As for today’s challenge, we are going to solve another JS.


Well, nothing interesting on the front page. How about the source code?


That’s it, the JS code lead us to the solution. We have to find the value of ul. As you can see, the index starts at .kr from the URL of the challenge.

Which mean the indexed characters are kr/challenge/js-1/. It contains 18 characters. Hence the final ul value is 18*30 = 540. Submit the value and complete the challenge.


Alternatively, try putting the code on JS compiler and change the ul variable before running it.

var ul="";
tags: - javascript

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