Senior Freelance Penetration Tester

Are you an experienced Freelance Senior Penetration Tester who thrives in the ever-changing world of Information Technology? Then we have exciting opportunities for you Senior Penetration Tester We are looking for a Senior Penetration Tester to execute high‐impact security assessments across infrastructure, applications, cloud and critical operational technologies. The goal is to perform threat‐led penetration testing aligned with DORA TLTP, identify vulnerabilities in complex environments, validate technical and business controls, and support the organization in strengthening its cyber resilience. In this role, you will apply deep offensive security expertise across IT and OT, while working closely with technical teams and stakeholders. Responsibilities Conduct infrastructure, application, cloud, and OT/ICS penetration tests in line with DORA TLTP, using white‐box, grey‐box, and black‐box approaches for internal and external attack scenarios. Perform full‐spectrum testing including discovery, enumeration, vulnerability mapping, exploitation, privilege escalation, lateral movement, network‐based testing, and (when authorized) DoS or host‐based techniques. Assess Windows, Linux, Solaris, enterprise networks, cloud environments (Azure), APIs, microservices, ESB/API‐gateway architectures, databases, and proprietary systems. Evaluate the security of SCADA/HMI systems and industrial protocols (BACnet, Modbus, OPC UA, Profinet, MQTT) across critical infrastructure. Validate technical and business controls, including anti‐fraud measures, and deliver regulator‐ready reports aligned with DORA. Collaborate with stakeholders, support remediation, and advise on improving architecture, segmentation, identity models, and secure development practices. Requirements 10+ years experience in infrastructure & application pentesting, plus 5+ years in critical infrastructure (ICS/SCADA/OT). Expertise in network technologies (Ethernet, Wi‐Fi, Fibre Channel, Bluetooth), authentication (Kerberos, NTLM, LDAP, SAML, OAuth, OpenID Connect), encryption, PKI, and defense‐in‐depth architecture across hybrid/cloud topologies. Strong skills in application testing: web apps, APIs, microservices, fat clients, middleware (ESB, API‐gateway), and secure development patterns (.NET, Java). Deep knowledge of Azure cloud security, hybrid connectivity, identity, segmentation, microservices, and interoperability. Proficient in Python, Bash, PowerShell and advanced pentest tooling (Nmap, Burp Suite, Nessus, Metasploit, Wireshark). Experience with threat‐led testing frameworks, especially DORA TLTP, including reporting to regulatory standards. Assets: reverse engineering (OSEE‐level or similar), malware development, red teaming, EDR evasion, custom C2 development. Analytical, independent, communicative, discreet, and collaborative mindset. Languages: English, French, and Dutch. Interested or know someone who fits? Let's connect You will work at a variety of large enterprises depending on your interest and your preferred way of working. At Brainbridge, we cover the IT landscape from A to Z. Brainbridge IT Staffing, part of Brainbridge Workforce Solutions, provides flexible IT Staffing solutions. Our goal is to be the highest rated talent sourcing partner for every client and professional. Throughout the years we built long-lasting relationships where we made a difference. We thrive for the absolute match, technically and personally, for both parties. We are specialized in freelance IT talent: from juniors with minimal work experience to senior experts with highly specific IT expertise. Is your passion IT? Are you dynamic, result-driven, and do you have a "can do" attitude? Join our Brainbridge success story and support our growth with your enthusiasm Looking forward to welcoming you to the world of Brainbridge