当て身 Atemi

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8 August 2020

Clicker

Challenge Source: Defcon 28 - Red Team Village CTF
Challenge Category: pwn

Pwn - Clicker

“All you have to do is score 10,000,000 to get the flag. Get Clicking!!!!!”

First we download clicker and make it executable.

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Well we can hit or hold enter to buy toilet paper and buy a multiplier once we have enough rolls. This resets the number of rolls to 0, and then we can buy 2 per “click”. Yep, there’s no way we’re getting to 10 million like this.

So what happens when we save?

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Just text? That seems easy enough to mess with!

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And then after messing around enough we realize there’s no way to load actually it, so this was likely a troll…

So how about gdb?

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Scrolling through, secret_function sure looks interesting. So lets run the program, then ctrl-c to break during execution:

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Now lets try to jump to the secret_function and see what happens:

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Tags: Defcon28-RTVCTF