Webgoat: Authentication & Access Control
Intermediate75 min5 objectives

Webgoat: Authentication & Access Control

Exploit authentication and authorization flaws in the Webgoat learning platform.

Briefing

### Scenario You are a general practitioner handling a realistic client engagement. For Webgoat: Authentication & Access Control, the client has provided a staging environment that mirrors production but is isolated to this lab. Your task is to demonstrate the core technique on the local target without touching external systems. The scenario is intentionally scoped to what you can verify inside the container. ### Environment and scope Use the Ubuntu 22.04 practice container. Working directory is `/home/student/lab-work` (create it with `mkdir -p`). Target is `127.0.0.1` and `127.0.0.1:8080` where a `python3 -m http.server` or service-specific daemon runs. Install only needed tools via `sudo apt-get update && sudo apt-get install -y curl, python3, nmap, openssl` then verify with `curl --version && python3 --version`. Credentials: `student:lab123` with `sudo` (created via `useradd` + `chpasswd` + `sudoers.d` as in `labs.service.ts:554`). Do not scan or query outside 127.0.0.0/8 or lab-work. Scope is strictly container-only; no external cloud, hardware, or nested container engines. ### Mission objective For Webgoat: Authentication & Access Control: install and verify tooling, prepare the local target (`127.0.0.1 and /home/student/lab-work`), execute the technique step-by-step, and collect evidence. Each walkthrough step produces a verifiable artifact (file, command output, or service state) that you will cite in your submission. ### Success criteria You have completed the lab when: - Tooling verification passes (`curl --version && python3 --version` returns expected version without error) - Local target is running and responds (`curl -s http://127.0.0.1:8080/` or `dig @127.0.0.1` or `tshark -r` shows expected output) - `solution.md` in `lab-work` documents each step's exact command, raw output excerpt, and your interpretation (what the output proves) - All flag answers are direct values from your local output (e.g., version string, status code, IP, header name) and no external hosts were targeted (`history | grep -E "nmap|dig|tshark|openssl|nikto|curl"` shows only 127.0.0.1) Runtime mode: portable artifact validation

Objectives

  • 1Prepare workspace and verify tooling
  • 2Prepare local target for Webgoat: Authentication & Access Control
  • 3Execute Webgoat: Authentication & Access Control technique
  • 4Capture evidence
  • 5Complete Login Bypass
  • 6Complete Access Hijacker
  • 7Tune and interpret
  • 8Compile and verify submission

Flags

Session Fixer+200 pts

Submit the verifiable output value for Session Fixer as produced by the local tool on 127.0.0.1 (e.g., version, status, IP, or header).

Login Bypass+200 pts

Submit the verifiable output value for Login Bypass as produced by the local tool on 127.0.0.1 (e.g., version, status, IP, or header).

Access Hijacker+200 pts

Submit the verifiable output value for Access Hijacker as produced by the local tool on 127.0.0.1 (e.g., version, status, IP, or header).

IDOR Explorer+200 pts

Submit the verifiable output value for IDOR Explorer as produced by the local tool on 127.0.0.1 (e.g., version, status, IP, or header).

JWT Forger+250 pts

Submit the verifiable output value for JWT Forger as produced by the local tool on 127.0.0.1 (e.g., version, status, IP, or header).