HowTo Hack Javascript Guessing Games

How to hack HTML/JS games where you must guess numbers or passwords

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Step 1: Get a Game

first you need a game, e.g. this one.
Open it with your borwser, i recommend Firefox.
I'll describe howto use firefox, not IE.

Step 2: Open Source of the Game!

right-click and select "View Page Source".
then search for the variable which you think is the number/etc you have to enter.

Step 3: Found It

we found a nice variable...

if we look at it, its a number between 0 and 1000, looks familiar... :-P

now enter javascript:alert(vaiable-name); into the address bar.
because our variable is called random_number, we enter javascript:alert(random_number);

Step 4: Running Our Little Script

ok now press RETURN, and we get a new window.
it should tell us the variable's value.

enter the value into the input-box.
if it was the right variable, we should have won.

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    7 Discussions


    Reply 10 years ago on Introduction

    i know, but because i use linux and firefox, i can't make an instructable for IE, because i can't get the screenshots of IE. and i don't like it.


    10 years ago on Introduction

    Hmm, I see this game was made by another Instructables member, Why dont you give credit to whoever made it.....

    4 replies

    Reply 10 years ago on Introduction

    yeah i found the game in his instructable, but @Nevermind: i dont have it "got", i dont host it, its the original URI... its not an instructable about this game, i just use it as an example