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Beginner Hint: About the Admin Bot

\n\n- In this challenge, you are given not only the web application itself, but also an admin bot.\n- The admin bot has a cookie containing the flag, and it opens a specified path using Headless Chrome.\n- Therefore, your goal is to make the admin bot trigger your payload and send the cookie value to an external server.\n- You can prepare your own server as the destination, or use an existing service that lets you receive and inspect HTTP requests.\n- If you are still not familiar with how to use the admin bot or how to inspect incoming requests, it may help to first solve [Fushigi Crawler](https://alpacahack.com/daily/challenges/fushigi-crawler?month=2026-01) and read its writeup.\n\n

Beginner Hint: How to approach

\n\n- `script` tags are not filtered, but they do not work in this challenge. When HTML is inserted using `innerHTML`, the browser does not execute any `script` tags in it.\n- You may want to use event attributes such as `onload` or `onerror` to trigger your payload. Can you use them without any whitespace characters?\n

\n","descriptionJa","共有は思いやりです\n

Beginner Hint: Admin Botについて

\n\n- この問題では、Webアプリ本体とは別に Admin Bot が用意されています。\n- Admin Bot はフラグ入りのCookieを持った状態で、指定されたパスを Headless Chrome で開きます。\n- そのため、目標は「Admin Bot に自分の用意したペイロードを踏ませて、Cookieの内容を外部へ送らせること」です。\n- 送信先は自分でサーバーを立ててもよいですし、HTTPリクエストを受け取って確認できる既存サービスを使っても構いません。\n- Admin Bot の使い方や、外部から受信したリクエストの確認方法がまだ曖昧なら、先に [Fushigi Crawler](https://alpacahack.com/daily/challenges/fushigi-crawler?month=2026-01) を解いてWriteupを読むことをおすすめします。\n\n

Beginner Hint: 解き方の方針

\n\n- `script` タグはフィルタされていませんが、この問題では使えません。`innerHTML` で HTML が挿入された場合、ブラウザはその中の `script` タグを実行しません。\n- ペイロードを発火させるには、`onload` や `onerror` のようなイベント属性を使うとよいかもしれません。これらは空白文字なしで使えるでしょうか？\n

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