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HackDefense understands how hackers work. And gives you insight into your exposure.


We love to understand modern digital technology down to the smallest details. We genuinely enjoy deciphering the code behind cyber attacks.


HackDefense provides insight into complex technical subjects for those responsible for IT Security, whether they have an IT background or not. We understand how it works, and we exist to communicate our knowledge to you in a way that helps you understand how to act.

Our team.

We’re a small team of Ethical Hackers and penetration testers, with experience since 1999 and knowledge of the latest hacking techniques.

That’s how we can recommend strategic and tactical initiatives to counter hacking attacks, as well as do technical deep-dives with your system administrators and developers.

Our highly-educated and certified Ethical Hackers find security weaknesses. And tell you, clearly and concisely, what that means for you and your organisation.

Mark Koek

Founder & CEO / Senior Ethical Hacker / IT Security Advisor

Kenneth Linzey

Senior Ethical Hacker / IT Security Advisor / CRTP / OSCE / OSCP / eWPT/ CRTE / CCSK

Rick Verdoes

Team lead Ethical Hacking / Senior Ethical Hacker / OSCE / OSCP / eWPT / eWPTX / eCPPT / eCPTX / CRTP

Danny de Weille

Ethical Hacker / IT Security Advisor / OSCE / OSCP / eWPT / eWPTX / eCPPT / CRTP

Jacqueline Quist

Management Assistant

Niels van Gijzen

Ethical Hacker / Developer / OSCP

Jony Schats

Ethical Hacker / IT Security Advisor / Security Officer / OSCP / eWPT / CRTP / CRTE / CARTP / eCPPT

Sander Meijering

Ethical Hacker / IT Security Advisor / OSCP / eWPT / eMAPT

Stan Plasmeijer

Assistant Security Scanning

Bob Hilgersom

Commercieel manager

Would you like to be part of this great team?

Are you a pretty good ethical hacker, if you say so yourself, or are you graduating and would you like to become an ethical hacker? HackDefense would love to talk to you.

Check our job openings