L'étape perdue

reverse linux x86/x64 FCSC 2026 solved on

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Description

The program provided performs operations on an IQ signal, allowing you to isolate information that I’m sure will interest you.

Unfortunately, its configuration file has been lost! Will you be able to reconstruct it after recovering the missing step? If so, you’ll need to listen very carefully! The IQ recording provided has been sampled at 250 kHz.

Files

Author

zrk

Challenge Instructions

  1. First, download docker-compose.yml:
    curl https://hackropole.fr/challenges/fcsc2026-reverse-etape-perdue/docker-compose.public.yml -o docker-compose.yml
  2. Launch the challenge by executing in the same folder:
    docker compose up
  3. Then, in another console, access the challenge with Netcat:
    nc localhost 4000
⚠️ Important: You must solve the challenge by interacting with the Docker container through the exposed network port. Any other way is not considered valid.

In case you encounter problems, please consult the FAQ.

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