Senior Security Specialist

Offensive Security Senior Security Specialist . Location Netherlands Hybrid (at least 3 days/week at our office in Zoetermeer) Employment Full-time Team Offensive Security You have years of experience breaking things that should not break. At DEFION, you get to shape your own role: tech lead, trainer, consultant, or deep specialist. Your call.

Conduct a full range of offensive security tests: web applications, infrastructure, cloud, mobile, and more Document findings in detailed reports and present results directly to clients Specialize in areas that match your interests: cloud security, red teaming, infrastructure, or security consulting/governance Provide security training, advise prospects, and mentor juniors and interns Develop and improve internal tooling when that is where your passion lies

Proven experience with pentesting and security assessments Broad IT knowledge: programming, networking, databases, Linux internals Knowledge of Cloud Security (AWS/Azure), Active Directory, mobile app security, OAuth/SAML, cryptography Experience with tools like Burp Suite, Nessus, or Nmap Strong knowledge of common vulnerabilities (XSS, CSRF, SQLi) and how to mitigate them A bachelor's or master's degree in a technical field (HBO/WO level) Ability to communicate technical findings clearly, both verbally and in writing

Published CVEs to your name Experience in security consulting or governance advisory

Why you will love working here Competitive package Competitive salary, permanent contract after probation, mobility budget or lease car, high-end laptop and phone. Personal training budget Invest in certifications, courses, or conferences. Grow technically and personally at your own pace. Diverse projects Short engagements (1-2 weeks) across many organizations and technologies. Never the same challenge twice. Shape your role Tech lead, trainer, tool builder, consultant: you decide where to take your career at DEFION. Great home base Game room, gym, daily lunch buffet, flexible hours. Parties, social events, and annual study trips. Nerdy colleagues Super social, tech-obsessed, down-to-earth. We share knowledge regularly and have fun while doing it. Send your CV and motivation. We respond within 3 business days. Name * Last name Email * LinkedIn profile Motivation * Send application By applying you agree to our privacy policy . Other open positions Research Sr. Vulnerability Researcher / Hardware Hacker Groundbreaking research at DEFION Research Labs. Full freedom, conference stage time. Defensive Security Medior SOC Analyst Sharp eye in our 24/7 MDR operations. Microsoft Defender and Sentinel. Sales Business Developer Help clients find the right security solutions. Hunter mentality, real impact.

Your expertise, your direction At DEFION, we work mostly with short projects of one to two weeks. That means you will work with many different organizations and application types in rapid succession. Some weeks it is a cloud environment, the next it is Active Directory, then a mobile app. Variety is built into the role. But beyond that, you shape this position yourself. Want to go deep on red teaming? Become a tech lead? Develop tooling? Train juniors? Advise clients on security strategy? We create the role that fits your strengths and ambitions.