Hacker101 CTF — Postbook Walkthrough

Title: Hacker101 CTF — Postbook Walkthrough

URL Source: https://medium.com/@ucarrcemre/hacker101-ctf-postbook-walkthrough-0fd40a698bba?source=rss------cybersecurity-5

Published Time: 2026-06-18T19:13:38Z

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# Hacker101 CTF — Postbook Walkthrough | by Ucarcemre | Jun, 2026 | Medium

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# Hacker101 CTF — Postbook Walkthrough

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Recently, I completed the Hacker101 Postbook challenge, a vulnerable blogging platform designed to demonstrate several common web application security flaws. Throughout the challenge, I encountered weaknesses related to authentication, authorization, hidden client-side parameters, predictable object references, and insecure session management.

This walkthrough explains the methodology I used to identify and exploit each vulnerability.

## Flag 0 — Weak Password Authentication

The first hint provided by the challenge