Capture the Flag

[un]prompted AI CTF

27–29 October 2026 · The Hibernia, San Francisco and online

All times Pacific. Flags look like unprompted{...}.

Send your team token on every request 
X-CTF-Team: your-team-name-lowercased-with-hyphens

Some challenges rate-limit per team. Everyone at the venue shares one network address, so without this header the whole room counts as one team and you’ll all start getting 429s within minutes.

Lowercase your team name and replace every character that isn’t a letter or digit with a hyphen — Bobby’s Tables 4 becomes bobby-s-tables-4. Set it once as a default in your client, harness or proxy.

When it runs

Tue 27 Oct, 10:00Kickoff, straight after the opening keynote.
Tue 10:00 → Wed 10:00Round 1 — the baseline set.
Wed afternoonHarness Village. Teams rebuild their tooling.
Wed 12:00 → Thu 12:00Round 2 — a reseeded set.
Thu 29 OctWinners revealed.

The competition runs continuously from Tuesday 10:00 to Thursday 12:00. Only the in-person room closes on the 28th, not the CTF.

Before kickoff

  • Make your team now. Team mode, maximum 4 players. Solo is fine — you still make a team, it just has one member.
  • Challenges stay hidden until kickoff. That’s expected, nothing is missing.
  • Pick your team name carefully — it’s also your X-CTF-Team header, and changing it mid-round means changing it everywhere.

Found something real?

Some of these are real, unfixed vulnerabilities

Some challenges involve defects in real, currently shipping software that haven’t been fixed or publicly disclosed. We don’t tell you which. Working out what’s real is part of the competition.

Tell us and we will ring the bell. Email aictf2026@unpromptedcon.org within 24 hours of finding something that wasn’t the intended solution. Reporting never costs you points — it can’t reduce your score or invalidate a solve.

Talk about it all you like at the conference: what you found, the kind of bug, how long it took, how you got there. Keep the reproduction steps and exploit code off the public internet until the vendor has had a chance to fix it — that’s the whole deal, and it’s time-limited. You keep the finding, the credit and the CVE.

The full terms are in the Coordinated Disclosure Policy, which you agreed to when you registered. If a challenge looks unsafe or unfair to keep running, put that in the subject line and we’ll act on it immediately.

Questions

Email aictf2026@unpromptedcon.org — the platform, the scoreboard, a challenge that looks broken, or whether something you’re about to try is in scope. If you’re not sure, ask first.

Don’t have the registration code? It goes to approved registrants before kickoff. If you haven’t received it, email us at the address above and we’ll send it to you.