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Writeup index

Reverse engineering challenges

Work out what a compiled program does without its source, then work backwards from the check to the input that passes it.

2,324 in the index. The 200 below are ranked by how many independent published solutions exist - which is the right order for learning, not for difficulty. A challenge with nine writeups gives you nine explanations of the same technique to compare; a harder one nobody documented gives you none.

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