Excalibra

Posted on Jul 25

How I Went From Interview Rejections to Building a 200+ Question Open‑Source Cybersecurity Resource

#cybersecurity #career #opensource #interview

And why I’m giving it away for free.

I remember the exact moment I realised I was doing interview prep all wrong.

I had just finished yet another technical interview that I thought went well. I knew the CIA triad. I could explain SQL injection. I’d even practised my STAR method answers.

Then the interviewer asked: “Walk me through how you’d respond to a ransomware outbreak across 200 servers.”

I froze.

Not because I didn’t know the answer — but because I’d never thought about interviews that way. I’d been memorising definitions when I should have been learning how security professionals actually think.

The Problem With Most Interview Prep

Here’s the reality: most cybersecurity interview resources are a mess.

Scattered PDFs that are years out of date
Random blog posts with conflicting answers
Paywalled courses that cost hundreds of pounds
Practice questions with no explanations — just “here’s the right answer, trust us”

Sound familiar?

I wasted months bouncing between these. Every time I thought I was prepared, a curveball question would expose another gap. I was building my knowledge on shaky foundations — and interviewers could tell.

So I did what any frustrated engineer would do.

I built my own.

Enter: 200+ Cybersecurity Interview Questions (Free & Open Source)

After six months of collecting, curating, and validating, I’m releasing what I wish I’d had from day one:

A free, open‑source collection of 200+ cybersecurity interview questions and answers.

Here’s what makes it different:

No fluff. Every question is practical and interview‑relevant.
Organised by domain — Red Team, Blue Team, Web Security, Incident Response, Network Security, Systems, Tools, and more.
Searchable live website — find topics instantly, no scrolling through a massive README.
Continuously updated — this isn’t a one‑and‑done PDF. It’s a living resource that grows with the community.
Completely free. No paywalls, no email sign‑ups, no tricks.

excalibra.github.io/cybersecurity-interview-questions

github.com/Excalibra/cybersecurity-interview-questions

What’s Inside?

The repository is organised into logical sections so you can focus on what matters most for your next interview:

Section	What You’ll Find
Red Team	Exploitation, evasion, deserialisation, WAF bypass, domain attacks, persistence
Blue Team	Incident response, log analysis, intrusion detection, traceability, system hardening
Web Security	SQLi, XSS, CSRF, SSRF, file uploads, logic flaws
Network Security	ARP, DNS, TCP/UDP, DDoS, OSI model, routing protocols, firewalls, SSL/TLS
Incident Response	Threat intelligence, malware detection, honeypots, forensic analysis
Internal Network Penetration	Lateral movement, domain controller attacks, golden/silver tickets, tunnelling
Systems	Windows/Linux hardening, privilege escalation, persistence detection
Tools	Nmap, sqlmap, webshells, proxies, tunnelling tools
Computer Networks	OSI model, TCP/IP fundamentals
Traceability & Traffic Analysis	Wireshark, traffic patterns, attack attribution

And yes — I recently added a dedicated Blue Team section with 70+ questions. Because defence matters just as much as offence.

Why Open Source?

I could have packaged this as a course or a paid PDF. But that’s exactly the problem I’m trying to solve.

Interview prep should be accessible to everyone.

By keeping it open source:

Anyone can use it, fork it, or contribute.
The community can catch mistakes and suggest improvements.
It stays relevant because it evolves with real‑world feedback.

If you find a question that’s unclear, an answer that could be better, or a topic that’s missing — open an issue or submit a pull request. This resource is for the community, and the community makes it better.

What People Are Saying

“I wish I had this when I was preparing for my first security role.”

— Anonymous Reddit user

“Finally, a resource that actually explains *why the answer is what it is.”*

— Early contributor

“The searchable live site is a game‑changer. No more scrolling through endless Markdown files.”

— Community member

How You Can Help

If this resource helps you, here are a few ways to give back:

⭐ Star the repository — it helps others discover it.
Share it — with your network, on LinkedIn, Reddit, or Discord.
Contribute — open an issue or PR with improvements.
Use it — and let me know what topics you’d like to see next.

One Last Thing

Interview prep isn’t about memorising trivia. It’s about building the mental models that help you think like a security professional.

This repository won’t guarantee you a job. But it will give you a structured, practical foundation — so when the interviewer throws a curveball, you’re ready.

Not because you memorised the answer.

But because you understand why it’s the answer.

Check it out here:

🔗 excalibra.github.io/cybersecurity-interview-questions

🔗 github.com/Excalibra/cybersecurity-interview-questions

If this helped you, please consider giving it a star ⭐ — it makes a huge difference in helping others find it.

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