Overview

bin200 is program that prints nonsense forever and prints the key if sent a SIGALARM.

Writeup

We take a look at this program and very quickly see that its doing tricky stuff with signals and otherwise loops forever, printing nonsense. Looking at catch_alarm, we see it de-obfuscates and prints a string depending on what signal it catches. As it turns out, it just dumps the key if sent a SIGALARM.

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% ./testa &
You probably thought that this deer was alive.
% kill -24 %1
MCA-225D4AFD
% kill -9 %1