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Senior Penetration Tester

CGI Wideopen, England, United Kingdom

remotefull-time
Posted Dec 8, 2025Apply by Mar 18, 2026

Role & seniority: Experienced Penetration Tester at CGI Cyber Security UK; potential progression to Team Leader or Principal Tester.

Stack/tools: Penetration testing across bespoke applications, cloud technologies, and mobile applications; broad cyber security services (risk assessments, vulnerability management, security architecture, incident response, monitoring, GRC, etc.) as context.

Top 3 responsibilities

  • Conduct professional penetration testing for commercial and public sector clients.

  • Assess security of bespoke apps, cloud, and mobile platforms; contribute to improvement of security posture and maturity.

  • Collaborate within an established tester team; potential progression to team leadership or senior technical roles; work at client sites or remotely.

  • Must-have skills: Relevant penetration testing qualifications (CHECK CTL/CTM, CCSAS, CCT/CCT Inf/CCT App, CSTL, QSTL, CRT, CSTM/QSTM, CPSA, OSCP); ability to obtain UK Security Clearance; experience across diverse test targets.

  • Nice-to-haves: Experience with multi-domain testing over 30 years’ client base; experience in risk/GRC and security testing in government, defence, healthcare, utilities, or financial sectors.

  • Location & work type: UK-based; flexible work arrangement with opportunities to work from home and at client sites across the UK; must meet UK clearance criteria.

Full Description

Position Description

CGI Cyber Security Team in the UK is one of the largest Cyber consultancies in the UK with around 300 members. The UK Cyber team works across a variety of domains including: Government, Defence, Critical Infrastructure, Healthcare, Utilities, Banking and Financial Services and Many more. At CGI you will get the opportunity to work across a number of domains and work in all areas of Cyber Security allowing you to grow and develop your career.

We offer full 360-degree services to our clients from initial consulting on a range of areas including Risk Assessments, Vulnerability Management, Accreditations (ISO27001, GDPR), GRC (Governance, Risk, Compliance), Security Architecture Design and Build (technical and Non-technical), Incident Response, Protective Monitoring Services, Penetration Testing and much more.

We take clients through a journey to improve their overall security posture and maturity to ensure they feel reassured in the Security control, measures and systems we have put in place in line with their requirements.

At CGI training and development is very important not only do we give you training to keep you up to date with the latest trends within an ever-changing landscape, but we also combine that training with your career ambitions, so we support you in taking your career anywhere you want it to go.

Our roles are only available if you hold or fulfil the criteria to obtain a UK Security Clearance.

Your future duties and responsibilities

An opportunity for an experienced penetration testers has become available due to growth, joining the CGI Cyber Security business unit, one of the largest groups of cyber security specialists in the UK.

CGI has a long established reputation in this area, undertaking rigorous testing for a variety of commercial and public sector clients for over 30 years. Experience of the assessment of bespoke applications, cloud technologies and mobile applications (on diverse mobile platforms) would be of an advantage.

You would join our established team of penetration testers with the possibility of progressing to team leader or principal tester positions.

You would be able to work flexibly, undertaking work at home and at client sites across the UK.

Required Qualifications To Be Successful In This Role

We would be interested to talk further if you hold any of the following qualifications

CHECK Team Leader (CTL) CHECK Team Member (CTM) CREST Certified Simulated Attack Specialist (CCSAS) CREST Certified Tester (CCT). Sometimes known as CREST Certified Infrastructure Tester (CCT Inf) or CREST Certified Web Application Tester (CCT App) Cyber Scheme Team Leader (CSTL) TigerScheme Qualified Security Team Leader (QSTL) Crest Registered Tester (CRT) Cyber Scheme Team Member (CSTM) TigerScheme Qualified Security Team Member (QSTM) CREST Practitioner Security Analyst (CPSA) Offensive Security Certified Professional (OSCP)

Together, as owners, let’s turn meaningful insights into action.

Life at CGI is rooted in ownership, teamwork, respect and belonging. Here, you’ll reach your full potential because…

You are invited to be an owner from day 1 as we work together to bring our Dream to life. That’s why we call ourselves CGI Partners rather than employees. We benefit from our collective success and actively shape our company’s strategy and direction.

Your work creates value. You’ll develop innovative solutions and build relationships with teammates and clients while accessing global capabilities to scale your ideas, embrace new opportunities, and benefit from expansive industry and technology expertise.

You’ll shape your career by joining a company built to grow and last. You’ll be supported by leaders who care about your health and well-being and provide you with opportunities to deepen your skills and broaden your horizons.

Come join our team—one of the largest IT and business consulting services firms in the world.

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