Our experts
Meet the people behind Adversify.
Get to know the specialists behind our work, their areas of expertise and the people beyond the technical qualifications.
The team
Who would work on my engagement?
Daniel Horvath
Co-founder and Senior Penetration Tester
Niche expertise
- Assumed Breach
- Enterprise Security
- External Perimeter
Dan is a senior penetration tester and offensive security consultant with over a decade of experience in cyber security. Beginning his career in a specialist police cyber crime unit, Dan went on to work for several security consultancies, delivering hundreds of penetration testing engagements across a wide range of industries and environments. His technical expertise lies in enterprise security, with a particular focus on Active Directory, Microsoft Entra ID, infrastructure and network penetration testing. He has a keen interest in understanding how weaknesses across different technologies can be combined to create real-world attack paths.
Rishabh Verma
Co-founder, Senior Penetration Tester and AI Innovator
Niche expertise
- AI Security
- Application Security
- Code review
Rish has spent more than a decade in offensive security, including leading CBEST red team engagements for major UK banks and specialising in payment systems security. He scopes tests around the attack surface and the attacker's objective, and develops multi-agent AI tools to support vulnerability discovery in code.
Gillian Vanhauwaert
Lead Penetration Tester
Niche expertise
- Application Security
- Internal enterprise
Gillian has worked in offensive security since 2019, specialising in internal infrastructure, web application, API and social engineering testing. She works closely with clients to understand their environments, explains findings in plain language and supports remediation, so that testing delivers meaningful improvements rather than just a list of risks.
Alasdair Gorniak
Penetration Tester
Niche expertise
- Application Security
- Bug bounty hunting
Alasdair came to penetration testing through bug bounties and responsible disclosure, reporting vulnerabilities to Microsoft and NASA, including CVE-2026-20841 in Windows Notepad. At Adversify he tests web applications and APIs, combining manual testing with AI-assisted tooling to cover more ground. Clients can expect thorough testing, clear evidence and reporting that turns findings into action.
Trust, verified
How do I know Adversify's testers are qualified?
Adversify Ltd is CREST-accredited for penetration testing and certified under Cyber Essentials. Our CREST accreditation and Cyber Essentials certification can be verified directly with the awarding bodies.
CREST
CREST accredits Adversify Ltd to deliver penetration testing services against its recognised technical and professional standards.
Check with CREST
Cyber Essentials
Cyber Essentials is a UK government-backed certification scheme designed to help organisations protect themselves against common cyber attacks.
Check with the NCSC
Offensive Security Certified Professional (OSCP)
A practical penetration testing certification earned through a hands-on examination covering reconnaissance, exploitation and privilege escalation.
Clients
What do their clients say?
Dan asked really relevant questions to obtain all the information he needed to provide us with a very thorough Pen Test. He worked really well with myself and the IT team at HSL and easily explained the findings in the report and steps on remediation.
From the very first conversation, his communication was clear, responsive, and tailored to the needs of an SME. He took the time to understand our requirements, explained the process in plain terms, and kept us updated at every stage.
Adversify recently conducted a comprehensive internal penetration test for our organisation, and the results exceeded our expectations. The team demonstrated exceptional expertise, thoroughly assessing our systems while maintaining a collaborative and professional approach throughout the process.
Could I join them?
We're hiring penetration testers
If you want to understand where an attack path leads, we would like to hear from you. Our testers have time to investigate beyond the first finding and explain what it means for the client.
What happens next?
Tell us what worries you. We will scope to it.
A penetration tester replies within one working hour and asks the questions needed to define the right scope.
- A written scope agreed before testing starts
- Typically 2 to 4 weeks from scope to delivery, depending on the scope
- CREST-accredited for penetration testing
- York based, UK wide
Your tester talks through the objectives, systems and constraints before preparing a quote.