Senior Offensive Security Specialist (Kubernetes & Container Security)

As a Senior Offensive Security Specialist (Kubernetes & Container Security) , you’ll dive deep into modern cloud and container platforms and other forms of “Infrastructure as Code” to uncover vulnerabilities, misconfigurations, and attack vectors before malicious actors perform them. You’ll tackle complex technical challenges where standard penetration testing ends and true specialized expertise begins.

What makes this role special is that such technology is often used by the industry’s major players, and a vulnerability in one place can ultimately have an impact far beyond it. The combination of in-depth offensive security knowledge with a direct impact on clients-or even our clients’ clients-often makes these assignments extra exciting. You’ll not only investigate how systems can be attacked, but you’ll also advise organizations on how to actually become more secure. In doing so, you’ll have the freedom to explore new attack techniques, develop tools, and further build your expertise to become a true leading specialist in the field.

No two assignments are the same. One week you might be investigating an international Kubernetes environment in the energy sector; the next week, you might be conducting an in-depth security assessment of an advanced CI/CD environment or advising a DevOps team on container security best practices.

What will you be performing?

• Conduct advanced Kubernetes and container security assessments.
• Penetration testing of cloud-native applications, APIs, and microservices.
• Identifying misconfigurations within Kubernetes clusters, container registries, and CI/CD pipelines.
• Investigating attack vectors within Azure, AWS, and Google Cloud environments.
• Simulate realistic attack scenarios on container and cloud platforms.
• Advising on secure-by-design, hardening, and DevSecOps principles.
• Developing custom tools, scripts, and security research.
• Presenting technical findings to clients and stakeholders.
• Coaching and mentoring colleagues on the offensive security team.

Who are you? You’re a specialist who looks beyond traditional penetration testing. You understand how modern cloud-native environments work and are driven to investigate new attack techniques, vulnerabilities, and security challenges., As a Senior Offensive Security Specialist, you’ll work on challenging projects as part of a team of experts who share your passion for cybersecurity.

You’ll share knowledge with your experienced colleagues, perform research together, and challenge each other technically. We believe that the best specialists never stop growing. That’s why we invest in training, certifications, attending conferences, and research. With us, you’ll find yourself in an environment where the level of expertise is demonstrably high.

Our specialists not only tackle complex security challenges but are also deployed to conduct investigations and assessments of systems and organizations of national importance. For example, our experts conducted source code and security investigations for the DigiD backend on behalf of Logius (https://www.tweedekamer.nl/downloads/document?id=2024D18965). In addition, our researchers were involved in security reviews of the Dutch CoronaMelder app (https://www.pentestreports.com/reports/secura/Coronamelder-REPORT-v1.0). Security assessments are also being conducted for systems operated by the Electoral Council (https://www.kiesraad.nl/site/binaries/site-content/collections/documents/2025/09/15/technical-security-assessment-transfer-platform/Kiesraad-Transfer-Platform-REPORT-v0.5.pdf). And there are many more exciting and impactful projects that we, of course, can’t tell you about just yet.

What sets us apart is that we don’t just claim our expertise-we have it independently verified. Quality, specialization, and thought leadership are deeply embedded in our organization. We actively share our knowledge within the cybersecurity community, publish research, and contribute to the development of standards within the field. This is also reflected in our accreditations. For example, we were the first cybersecurity company in the Netherlands to receive the CCV Penetration Testing certification, and to this day we remain involved in the ongoing development of this certification.

For professionals who want to surround themselves with the best specialists, work on socially relevant projects, and continuously deepen their expertise, we offer an environment where you can truly make a difference.

• Several years of experience in offensive security, penetration testing, or red teaming.
• In-depth knowledge of Kubernetes, Docker, and container security.
• Experience with Azure, AWS, or Google Cloud.
• Knowledge of Linux, networking, and automation.
• Experience with Python, Bash, or Go.
• Strong communication skills in Dutch and English.
• OSCP, OSEP, CRTO, CKA, or comparable certifications.
• Experience with Kubernetes hardening and container escape techniques.
• Experience with scalable Infrastructure-as-Code platforms such as Docker Swarm or Ansible.