It’s a pretty weird task that involves moving the “@” symbol to “X” symbol around the “map” from the dots, but you need to change the Player has flag parameter from 0 to something else.
To do this, we need to trigger a segmentation fault.
First, let’s try to just get to the end. Let’s create a payload so we don’t have to type characters manually:
We get “You win!” and that’s all we got (parameter Player has flag: 0)
I was poking aroung and found, that if you move to the far left, you will be moved up one line near the far right.
So you can move to the right as if reading a book and you will arrive at “X” !
IMPORTANT
Let’s move to the upper left corner and go beyond the map:
What we have done:
-
reached the upper left corner
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moved 4 to the left (if 5, the program crashes)
-
turned 1 step back to the right
Now, with this value Player has flag: 46, we need to get to the end:
picoCTF{gamer_m0d3_enabled_f4f6ad7d}