Forbidden executable
100 points Hard

Hey, I've got tiny binary, I cannot reverse it, even debug it till its end, but running it outside debugger causes no trouble. I'm wondering what is the value of ECX register when the program exits ? Provide it as decimal value in format CTFlearn{XXX}. Program is well written and not cause any exceptions or access violations in normal execution.

impossible_disasm.exe
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Reverse Engineering ยท domin568
37 solves
Rating 4.23
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Davidpb

5 months ago

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Canlex

2 years ago

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EaZyq

3 years ago

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flag is the value in cx not ecx?

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Ichild

3 years ago

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Not much fun, but this program's really amazing, it's so delicate.

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Rivit

4 years ago

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Educating, interesting, learned a lot of new cool stuff. Thanks!

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Caillou

4 years ago

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b4el7d

4 years ago

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i think this EXE contains trojan Zpevdo.A Check this file.

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domin568

4 years ago

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False positive, maybe because there are anti debug tricks out there.

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Caillou

4 years ago

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The file is safe. Did the same alerts perhaps du to signature.

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Tearth

4 years ago

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Caillou

4 years ago

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domin568

4 years ago

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Yeah, I cannot change it, there is no such possibility for me as challenge onwner. If somebody sees it from administration please change ECX to CX in challenge description.

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