Penetration Tester jobs in United Kingdom

Junior Penetration Tester within the CGI Cyber Security Team in the United Kingdom. Main location: United Kingdom, England - South East, Reading. Position ID: J0425-0107. Employment Type: Full Time.

CGI Cyber Security Team in the UK is one of the largest cyber consultancies in the UK with around 1700 members. The team works across Government, Defence, Critical Infrastructure, Healthcare, Utilities, Banking and Financial Services and many more. This role offers the opportunity to work across multiple domains and areas of Cyber Security to grow and develop your career. CGI was recognised in the Sunday Times Best Places to Work List 2025 and named one of the World’s Best Employers by Forbes. We offer a competitive salary, pension, private healthcare, and a share scheme (3.5% + 3.5% matching). We are committed to inclusivity and hold a Gold Award for supporting the Armed Forces Corporate Covenant. You will be part of an open, friendly community of experts with access to training and development to support your career growth.

An opportunity for a CHECK Team Member or Infrastructure CHECK Team Leader is available within the Cyber Security business unit. 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. Due to the secure nature of the programme, you will need to hold UK Security Clearance or be eligible to obtain clearance.

You would join an 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.

We offer 360-degree services to clients from initial consulting on areas including Risk Assessments, Vulnerability Management, Compliance (ISO27001, GDPR), GRC (Governance, Risk, Compliance), Security Architecture Design and Build (technical and non-technical), Incident Response, Protective Monitoring, Penetration Testing and more. We help clients improve security posture and maturity, ensuring security controls and systems align with their requirements.

CGI emphasizes training and development, pairing training with career ambitions to support your growth and direction.

Required qualifications:

• OSCP / OSCP+ certification
• Willingness to learn

• Previous penetration experience is highly desirable but not essential as training will be provided

• Cyber
• Security Monitoring AI
• Security Operations Center

Together, as owners, let’s turn meaningful insights into action. Life at CGI is rooted in ownership, teamwork, respect and belonging. You’ll be invited to be an owner from day 1 as we work together to bring our Dream to life as CGI Partners. You’ll develop innovative solutions, build relationships with teammates and clients, and access global capabilities to scale your ideas and broaden your horizons. You’ll be supported by leaders who care about your health and well-being and provide opportunities to grow.

Join one of the largest IT and business consulting services firms in the world.