The Secure Code Review Challenge — Solution #1: Schooled (One Whitespace Character Away From Admin)
The full solution to Challenge #1: Schooled — walking through the review methodology, finding the planted vulnerability, proving it's exploitable, and fixing it without breaking functionality.
This is part of the Secure Code Review Challenge: a biweekly series of full, realistic applications — each with its own database, backend, and UI — with a vulnerability planted on purpose, based on a real-world CVE or writeup. Unlike snippet-based practice, these challenges let you practice the full secure code review process: understanding architecture and entry points, identifying relevant vulnerabilities, checking where they're mitigated, confirming exploitability, and proposing a fix.
📌 Repo: https://github.com/mohamed-osama-aboe...
📌 Challenge #1: Schooled: https://github.com/mohamed-osama-aboe...
📌 Solution #1: Schooled: https://github.com/mohamed-osama-aboe...
📌 Try Challenge #2 now: https://github.com/mohamed-osama-aboe...
New drops land every two weeks — each one bundles the previous challenge's solution alongside a brand new challenge, and each challenge and solution is a assigned to new relase, so you can watch the repo (Settings → Watch → Custom → Releases) to get notified as new challenges and solutions go live.
🔹 Full applications, not snippets: every challenge ships with its own database, backend, and UI — you review it the way you'd review a real codebase
🔹 Real-world grounding: the planted vulnerabilities are based on actual CVEs and vulnerability writeups, not invented bugs
🔹 A repeatable methodology: understand the architecture and entry points, identify relevant vulnerabilities (business logic, source-sink, injection, etc.), check where they're mitigated, confirm exploitability, then propose a fix
🔹 A template you can use: the repo includes a suggested methodology template to fill out for each challenge — use it as-is or adapt your own
🔹 No spoilers: work through each challenge privately until the solution is published, so you don't spoil it for others still solving it
⏱️ Chapters:
00:00 – Intro & Overview of Challenge #1: Schooled
1:39 – Running the App Locally (Docker Compose Walkthrough)
4:09 – Recapping the 7-Step Review Methodology
6:38 – Step 1: Application Scope & Architecture
12:35 – Step 2: Identifying Entry Points
13:08 – Step 3: Identifying Dangerous Sinks
14:17 – Step 4/5: Threat Model & Mitigation Review — Business Logic (Auth, RBAC, Role Assignment)
28:46 – Step 4/5 (cont.): Threat Model & Mitigation Review — Source-to-Sink (XSS, SQLi, CSRF)
35:51 – Step 6: Finding the Vulnerability (Privilege Escalation via Trailing Space)
40:21 – Exploiting the Vulnerability (Live PoC)
42:34 – Step 7: Suggested Fix
44:08 – Real-World Grounding (CVE Parallel: HashiCorp Vault)
44:54 – Wrap-Up & Challenge #2
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