Senior Penetration Tester

About Us

Integrity360 is the largest independent cyber security provider in Europe, with a growing international presence spanning the UK, Ireland, mainland Europe, Africa and the Caribbean. With over 700 employees, across 12 locations, and six Security Operations Centres (SOCs)—including locations in Dublin, Sofia, Stockholm, Madrid, Naples and Cape Town—we support more than 2,500 clients across a wide range of industries.

Over 80% of our team are technical experts, focused on helping clients proactively identify, protect, detect and respond to threats in an ever-evolving cyber landscape. Our security-first approach positions cyber resilience as a business enabler, empowering organisations to operate with confidence.

At Integrity360, people come first. We invest heavily in learning, development and progression, fostering a dynamic culture where innovation, collaboration and continuous growth are at the heart of what we do. If you're ready to take your cyber security career to the next level, we’d love to hear from you.

Role Overview

We’re looking for a Penetration Tester with at least 5 years of real-world professional experience, fully independent, with consultancy and tutoring skills and experience.

In this role, you’ll support and deliver testing projects (web, infra, cloud, AD, and mobile and not limited to), guided by experienced technical leaders. You’ll be involved in pre-sales activities, travelling onsite on customer environments and delivering high quality services.

Job Role / Responsibilities

As a Senior Security Tester, you will deliver advanced penetration testing and security assessments across a wide range of environments and technologies. You will also contribute to internal capability development, collaborate with other departments, and represent Integrity360 in client engagements and technical forums.

This role blends deep technical expertise with excellent communication and documentation skills.

Core Responsibilities:

Security Testing & Delivery

• Perform advanced manual penetration tests and technical security assessments (web, mobile, infrastructure, cloud).
• Execute Red Team or assumed breach engagements as part of a team or independently.
• Identify, exploit, and document vulnerabilities in complex systems, clearly articulating risk and remediation to stakeholders.
• Review application architectures and source code for security weaknesses.

Reporting & Communication

• Produce high-quality technical reports and executive summaries tailored to various audiences.
• Present findings to clients and internal stakeholders in a clear and professional manner.

Research & Innovation

• Continuously research new vulnerabilities, attack techniques, and tools to stay ahead of evolving threats.
• Contribute to the development of internal methodologies, tools, and automation scripts.

Internal Support & Mentoring

• Act as a mentor for junior and mid-level testers, supporting their growth and development.
• Support the testing team in delivery planning, documentation, and knowledge sharing.

Cross-Team Collaboration

• Work closely with SDMs, Project Managers, and other technical teams to ensure smooth delivery.
• Support Sales and Marketing teams with technical insights for proposals, events, or webinars when needed.

Desired Skills

• Solid experience in information security
• Industry experience working in Dev/Admin/Engineer field
• Industry experience working in Information security field as a penetration tester
• Development and/or source code review experience in C/C++, C#, VB.NET, ASP, PHP, Java, Python or Ruby
• Strong Unix, Windows and networking security skills 
• Familiarity with general application and network security concepts 
• Excellent communication skills 
• Manual penetration testing experience above and beyond running automated tools 
• Experience developing custom scripts or tools used for vulnerability scanning and identification

• In depth networking knowledge (ports, protocols, firewalls, routing, VPN, MPLS, BGP, OSPF, IPv6, TOR)
• Understanding of development frameworks
• Broad understanding of hosting /cloud environment
• Broad understanding of SIEM & Defensive Technologies.
• Understanding of Security Auditing tools
• Ethical hacking experience
• Intrusion prevention experience
• Report writing experience
• Presentation skills
• Scripting/coding, sys admin or networking experience
• Understanding of programming methodologies
• Understanding of quality management and project management principles
• Knowledge of advance cloud architecture

Certifications/Qualifications

• Security Clearance or local vetting (as required by region or client sector)
• Relevant certifications such as OSCP, OSCE, OSEP, CRTO, CREST, or equivalent
• Bachelor’s degree in Computer Science, Cybersecurity, or related field (or equivalent hands-on experience)

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