Senior Attack Engineer, Kubernetes

Get to Know Us Horizon3 is a fast-growing, remote cybersecurity company dedicated to the mission of enabling organizations to proactively find and fix and verify exploitable attack vectors before criminals exploit them. Our flagship product, the NodeZeroTM platform, delivers production-safe autonomous pentests and other key assessment operations that scale across the largest internal, external, cloud, and hybrid cloud environments. NodeZero has been adopted by organizations of all sizes, from small educational institutions to government agencies and Global 100 enterprises. It is used by ITOps/SecOps teams, consulting pentesters, and MSSPs and MSPs. We are a fusion of former U.S. Special Operations cyber operators, startup engineers, and formerly frustrated cybersecurity practitioners. We're committed to helping solve our common security problems: ineffective security tools, false positives resulting in alert fatigue, blind spots, "checkbox” security culture, cybersecurity skills shortage, and the long lead time and expense of hiring outside consultants. Collectively, we are a team of learn it alls, committed to a culture of respect, collaboration, ownership, and results. About The Role We’re looking for a senior offensive security engineer to lead the development of Kubernetes attack capabilities in NodeZero. You’ll research how attackers move from a compromised workload or identity through and beyond a cluster, and turn that research into safe, repeatable capabilities. You’ll own complex work from attack research and technical design through integration and customer-facing proof, while helping set the direction for Kubernetes coverage across cloud and self-managed environments. This is not a maintenance role. You'll serve as the technical lead helping define Horizon3 's Kubernetes offensive security strategy and will have a first-hand influence on how Kubernetes attacks are integrated into the platform. What You’ll Do

• Lead offensive security research into Kubernetes clusters, workloads, identities, configurations, and cloud-connected environments.
• Design and build production-quality Python attack capabilities that model realistic attacker perspectives, including an assumed-breach foothold in a pod or workload.
• Develop and validate attack paths involving Kubernetes RBAC, service accounts and credentials, workloads and pods, secrets, cluster and node boundaries, network reachability, and integrations with cloud identities and managed Kubernetes services.
• Assess Kubernetes security weaknesses and determine whether they create meaningful, provable impact; build safe validation and negative testing into the capability.
• Own technical planning for substantial Kubernetes initiatives: identify coverage gaps, prioritize research, make design trade-offs, and coordinate delivery with Product, platform, and engineering partners.
• Integrate attack content into NodeZero’s execution and results flows so customers receive reliable evidence and clear explanations of the paths found.
• Review code and designs, establish quality expectations, mentor teammates, and share Kubernetes offensive-security expertise across the team.
• Document methodologies, assumptions, limitations, and test approaches; contribute to internal and external technical enablement where appropriate.

What You’ll Bring

• Deep hands-on experience with Kubernetes security and offensive testing of containerized environments.
• Expert level understanding of Kubernetes architecture and identity and authorization controls, especially RBAC, service accounts, workloads, and cluster boundaries.
• Strong Python engineering skills and experience productizing security research into reliable automation.
• Experience with penetration testing, red teaming, vulnerability research, container security, or offensive security tooling.
• Ability to lead ambiguous, cross-functional technical work and communicate attack paths and impact clearly.
• A strong safety and product mindset: you can distinguish a theoretical weakness from a reproducible, actionable finding and build capabilities that behave predictably.
• A record of owning complex technical projects, making sound trade-offs, and communicating clearly with technical and non-technical partners.
• Strong written communication and a habit of documenting research and design decisions.

What Sets You Apart

• Experience with EKS, GKE, AKS, OKE, or other managed Kubernetes services.
• Knowledge of Linux, containers, cloud workload identity, Kubernetes operators, Helm, or infrastructure as code.
• Experience with network attack paths, container escape research, or cloud-to-cluster attack paths.
• Contributions to open-source security tooling, public research, conference talks, or vulnerability disclosure.

Travel Required We are a fully remote company, and this job may require up to 10% of travel to be successful. Perks of Horizon3

• Inclusive Team: We value diversity and promote an inclusive culture where everyone can thrive.
• Growth Opportunities: Be part of a dynamic and growing team with numerous career development opportunities.
• Innovative Culture: Work in a collaborative environment that encourages creativity and out-of-the-box thinking.
• Hybrid & Remote Work: We embrace a mix of remote and hybrid work models depending on role and location, including our Chicago office, where some roles require regular in-office presence.
• Competitive Compensation: We offer competitive salary, equity and benefits. Our benefits include health, vision & dental insurance for you and your family, a flexible vacation policy, and generous parental leave.

Compensation and Values At Horizon3, we believe that our people are our greatest asset, and our compensation philosophy reflects this core value. We are committed to fostering an environment where all employees feel valued, respected, and rewarded for their contributions. Our compensation structure is designed to be fair, competitive, and transparent, ensuring that every team member is recognized and compensated equitably across roles, levels, and locations. In accordance with various State’s transparency regulations, we provide the following salary range information for this position:

• Base salary range: $206,278 - $242,680. The exact salary will be determined based on the selected candidate’s location, qualifications, experience, and relevant skills.
• Additional compensation: All full-time roles are eligible for an equity package in the form of stock options.

You Belong Here Horizon3 is not just an equal opportunity employer - we are a community that values diversity, equity, and inclusion as fundamental principles of our culture and success. We are dedicated to fostering a workplace where everyone feels welcome and respected, regardless of race, color, religion, sex, national origin, age, disability, veteran status, sexual orientation, gender identity or expression, genetic information, marital status, or any other legally protected status by law. Our commitment to diversity and inclusion means we strive to attract, develop, and retain a workforce that reflects the varied communities we serve. We believe that diverse perspectives drive innovation and strengthen our ability to create cutting-edge cybersecurity solutions. At Horizon3, every team member is valued and supported in an environment that encourages personal and professional growth. We welcome candidates from all backgrounds and experiences, and we encourage all qualified individuals to apply. Come be a part of Horizon3, where your unique contributions are recognized, and your potential is limitless. Other Duties Please note this job description is not designed to cover or contain a comprehensive listing of activities, duties or responsibilities that are required of the employee. Duties, responsibilities, and activities may change at any time with or without notice. Application Note In any materials you submit, you may redact or remove age-identifying information such as age, date of birth, or dates of school attendance or graduation. You will not be penalized for redacting or removing this information.