JWT/admin.html at main · Heyaa28041/JWT · GitHub

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<!DOCTYPE html>
<html>
<head>
  <title>Admin Panel</title>
</head>
<body>
  <h1>Admin Panel</h1>
  <div id="message"></div>

  <script>
    // Helper: Base64 decode
    function base64Decode(str) {
      try {
        return atob(str);
      } catch {
        return "";
      }
    }

    // Get cookie value
    function getCookie(name) {
      const match = document.cookie.match(new RegExp('(^| )' + name + '=([^;]+)'));
      return match ? match[2] : null;
    }

    // Double decode the token
    const tokenDouble = getCookie("token");
    if (!tokenDouble) {
      document.getElementById("message").innerText = "No token found.";
    } else {
      const onceDecoded = base64Decode(tokenDouble);
      const twiceDecoded = base64Decode(onceDecoded);

      // JWT format: header.payload.signature
      const parts = twiceDecoded.split(".");
      if (parts.length === 3) {
        const payload = JSON.parse(base64Decode(parts[1]));
        if (payload.role === "admin") {
          document.getElementById("message").innerText = "Welcome Admin! Flag: HEYAAJWTMASTER";
        } else {
          document.getElementById("message").innerText = "Access Denied. You're not admin.";
        }
      } else {
        document.getElementById("message").innerText = "Invalid token.";
      }
    }
  </script>
</body>
</html>