Hey, I'm
Tibo Claesens.
Cybersecurity professional based in Belgium. I do pentesting, security audits and help organisations understand where they're vulnerable — and what to do about it.

About
I started my career as a web application developer at Imengine, where I learned how applications really work — and where they tend to break. From there I moved into cybersecurity at Deloitte as a Senior Cyber Security Professional, working on pentesting, audits and security advice for large organisations in Belgium and beyond. I later founded ZeroBit to bring that same level of advice to smaller organisations that don't have a full security team in-house.
Today I focus on what I enjoy most: pentesting web applications and networks, security research, and writing about what I learn along the way. I love working with SMEs and technical teams that want a concrete answer to where they stand — and what the first, realistic steps are to become more resilient against real threats.
Current projects
What I do
Pentesting
Finding vulnerabilities in web applications, APIs, networks and cloud infrastructure before someone else does. Each engagement comes with a clear report, reproducible findings and concrete remediation steps your team can pick up immediately.
Security advising
Helping teams and leadership understand their risk posture and take practical steps to improve it — from baseline assessments and risk analysis to NIS2, ISO 27001 or customer audit preparation.
Writing
Sharing what I learn through honest, jargon-free articles on this blog: lessons from real engagements, explanations of new vulnerabilities, and practical tips for anyone who wants to make a difference without a dedicated security team.
Latest posts
All posts →28 Feb 2024
How much does a Pentest cost?
Although I haven't really been asked this question yet, it might be something on your mind. Our core value of custom work doesn't allow us to put a standard price on a pentest.
21 Feb 2024
How does the sales process work at ZeroBit?
We are straightforward people. No unnecessary fuss, please. Want a pentest? We can do that. Want a quote? We can do that too.
14 Feb 2024
Valentine's Special from the Archives: Heartbleed.
Heartbleed (CVE-2014-0160): A Deep Dive into the OpenSSL Vulnerability That Shook the Digital World. Since it's Valentine's Day, we're staying on theme.
Want to talk?
Whether it's a project, a question, or just a chat about security — feel free to reach out.
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