COMMANDer

Bahtera 3108 2025 web writeup for COMMANDer, inspecting the pilihan API response and submitting the recovered command to the check endpoint.

By 0xG10D | Last updated: August 30, 2025 | 1 minute read
Medium #ctf#bahtera-3108#web-exploitation#api

Challenge Overview

  • Challenge: COMMANDer
  • Category: Web
  • Points: 100

Terminal lama ini menyimpan biodata seseorang bersama rahsianya. Namun, rahsia itu hanya akan terbuka kepada mereka yang tahu menggunakan arahan yang tepat. Mampukah anda menguasai terminal ini untuk membongkar kebenaran?

COMMANDer terminal page

COMMANDer terminal interaction

Inspect the API

Open the browser’s developer tools, select the Network tab, refresh the page, and inspect the request to /api/pilihan. The required value is present in its JSON response.

The api-pilihan JSON response

Submit the Command

Send the recovered command to /api/check as JSON:

curl -s -X POST http://<TARGET>/api/check \
  -H "Content-Type: application/json" \
  -d '{"command":"RAHSIA: OperationOatmeal","step":1}'

COMMANDer flag response

Flag

3108{0p3R4T10n_O@Tm34l_1bR4h1M_1sM@1L}

Authorized security practice only. These notes are for lab, CTF, and explicitly permitted environments.