Rules

  1. The purpose of the competition is to have fun, learn about digital signal processing, and improve your GNU Radio skills.
  2. You can compete individually or as a team.
  3. Collaboration among participants is allowed and encouraged.
  4. Flags are generally formatted as flag{...} but the format may differ depending on the limitations of the signal that carries the flag. There should always be some indication that what you're looking at (or listening to) is a flag. If you're in doubt about the flag format, ask the organizers for help.
  5. Tools other than GNU Radio may be used. For instance, you may find Gqrx and inspectrum helpful. The Signal Identification Wiki is also a great resource.
  6. One signal may carry multiple flags. Look carefully!
  7. Solving one challenge will sometimes unlock additional challenges. New challenges may also be added as the competition progresses.
  8. The competition begins on Monday, September 26 at 13:00 EDT (17:00 UTC) and ends on Thursday, September 29 at 16:00 EDT (20:00 UTC).
  9. Remote participation is allowed, however some challenges involve over-the-air signals that can only be received on-site at the GRCon venue. These challenges will be marked with "[on-site]" in the challenge or category name. Remote participants can collaborate with on-site participants to solve these challenges.
  10. Participants are encouraged to create and submit their own challenges. As a bonus, contributors are allowed to claim the points for any challenges they create. Contact @argilo:gnuradio.org on Matrix or email ctf@gnuradio.org if you're interested.
  11. View the source of this page to get your first flag.