Epoch Guardian

Flag: HACKDAY{a9f3c1e8b2d4_5e7d0c19fa33_c4b7aa10d92f}

Challenge

Description

---

December 31st, 1999 — one minute to midnight. Millennium Systems' Project Époch refuses to fail during the Y2K rollover. A mysterious chatbot claims to be the Guardian of Époch and blocks any request that isn't "destined".

Convince the Guardian you are the chosen operator.

*- This is a deterministic bot (no AI guessing). *- The proof is not guessable: clues are provided by the service itself.

https://wxx3rptcb9.hackday.fr

Ce challenge tourne sur un docker et n'est pas disponible

Solution

Fragment A : dans le code source de la page /

      bubble.appendChild(head);
      bubble.appendChild(pre);
      row.appendChild(bubble);
      chatEl.appendChild(row);
      chatEl.scrollTop = chatEl.scrollHeight;
    }
// Load chat history from server                                   FRAG_A = "a9f3c1e8b2d4" 
    async function loadHistory() {
      const r = await fetch('/api/history');
      const data = await r.json();
      chatEl.innerHTML = '';
      (data.history || []).forEach(m => addMessage(m.role, m.content));
    }

---

Fragment B : le bouton "Crawler Rules txt" sur la page / donne une indication sur l'existence de /rules.txt

User-agent: *
Disallow: /backups/
# PROPHETIC_FRAGMENT_B: 5e7d0c19fa33

---

Fragment C : le bouton "Heartbeat" sur la page / mène sur /healthz. Dans les headers de réponse, on trouve x-epoch-heartbeat

Server: cloudflare
Server-Timing: cfExtPri
X-Epoch-Heartbeat: c4b7aa10d92f