Lead Pentester - SC Cleared

CBSbutler; West of England; Hybrid; GBP 80,000 - 100,000; Full time

Benefits offered by this job

Hybrid working

Company benefits package

Training & certification support

Career development opportunities

Job summary

CBSbutler is seeking an experienced Lead Penetration Tester / CHECK Team Leader (CTL) to join its Offensive Security team in Bristol on a hybrid model. You will own complex security engagements across Defence, Government and critical infrastructure, mentoring juniors and shaping service offerings.

You will lead testing across infrastructure, web apps, APIs, cloud and OT, while reporting findings and collaborating with clients to remediate risks.

Qualifications

• Current CREST CHECK Team Leader (CTL) qualification - essential.
• Strong hands-on penetration testing experience across infrastructure, applications, cloud or complex environments.
• Experience planning, leading and delivering penetration testing engagements.
• Excellent technical report writing and the ability to communicate findings to technical and non-technical audiences.
• Strong stakeholder management and client-facing consulting skills.
• Good understanding of cyber security frameworks, standards and best practices.
• Experience with scripting or automation using Python, PowerShell, Bash or similar.
• Strong analytical and problem-solving skills.
• Ability to obtain SC Security Clearance, potentially progressing to higher levels of clearance.

Responsibilities

• Lead and deliver penetration testing engagements across infrastructure, web apps, APIs, cloud, OT.
• Plan and scope testing engagements in line with CHECK standards and industry best practices.
• Provide technical leadership and QA across penetration testing activities.
• Produce detailed technical and executive reports with vulnerabilities and remediation.
• Collaborate with customers and stakeholders to meet security requirements.
• Mentor junior testers and CHECK Team Members.
• Contribute to development of methodologies, tooling and services.
• Stay updated on threats and attack techniques.

Skills

CTL qualification

Penetration testing

Leadership

Report writing

Stakeholder management

Security frameworks

Scripting (Python/PowerShell/Bash)

Analytical thinking

Security clearance

Job description

Lead Penetration Tester / CHECK Team Leader (CTL)

Location: Bristol - Hybrid (2 days per week onsite)

Salary: £80,000 - £100,000 per annum + Company Benefits

Employment Type: Permanent

The Opportunity

We are looking for an experienced Lead Penetration Tester / CHECK Team Leader (CTL) to join a growing Offensive Security team within a leading defence and cyber security environment.

This is an exciting opportunity for a technically strong penetration testing professional to take ownership of complex security engagements across Defence, Government and Critical National Infrastructure.

You’ll be working on challenging, high-assurance environments, helping to identify vulnerabilities, strengthen security controls and protect critical systems.

This position offers much more than hands-on penetration testing. You’ll have the opportunity to provide technical leadership, mentor junior consultants, contribute to service development and help shape the future of an expanding Offensive Security capability.

Key Responsibilities

• Lead and deliver penetration testing engagements across infrastructure, web applications, APIs, cloud, wireless networks and Operational Technology (OT).
• Plan and scope testing engagements, ensuring alignment with NCSC CHECK standards and industry best practices.
• Provide technical leadership and quality assurance across penetration testing activities.
• Produce detailed technical and executive reports, clearly communicating vulnerabilities, business risks and remediation recommendations.
• Work closely with customers and key stakeholders to understand security requirements and deliver effective testing solutions.
• Support and mentor junior penetration testers and CHECK Team Members.
• Contribute to the development of offensive security methodologies, tooling, automation and service offerings.
• Stay up to date with emerging threats, attack techniques and vulnerabilities.

Essential Skills & Experience

• Current CREST CHECK Team Leader (CTL) qualification - essential.
• Strong hands-on penetration testing experience across infrastructure, applications, cloud or other complex environments.
• Experience planning, leading and delivering penetration testing engagements.
• Excellent technical report writing and the ability to communicate findings to technical and non-technical audiences.
• Strong stakeholder management and client-facing consulting skills.
• Good understanding of cyber security frameworks, standards and best practices.
• Experience with scripting or automation using Python, PowerShell, Bash or similar.
• Strong analytical and problem-solving skills.
• Ability to obtain SC Security Clearance, potentially progressing to higher levels of clearance.
• Willingness to travel to customer sites when required.

Desirable Experience

• Existing SC or DV Security Clearance.
• Experience working within Defence, MOD, Government or National Security environments.
• Additional certifications such as CREST CCT, OSCP, OSEP, OSWE or CRTO.
• Cloud penetration testing experience across AWS, Azure or GCP.
• Operational Technology (OT/ICS) security testing experience.
• Experience developing penetration testing tools, automation or frameworks.
• Knowledge of NCSC CAF, NIST, ISO 27001 and MITRE ATT&CK.
• Experience mentoring junior penetration testers or conducting technical quality assurance.

What's on Offer?

• Competitive salary of £80,000 - £100,000 per annum.
• Hybrid working - just 2 days per week onsite in Bristol.
• Company benefits package.
• Access to industry-recognised training, conferences and professional certification support.
• Opportunities to work on technically challenging projects across Defence, Government and Critical National Infrastructure.
• Exposure to a wide range of technologies, security environments and emerging threats.
• Opportunities to contribute to offensive security research, tooling and innovation.
• Genuine scope to influence technical direction, service development and the growth of the wider Offensive Security function.

Interested?

If you’re an experienced penetration tester with a current CHECK Team Leader (CTL) qualification and are looking for a role offering technical challenge, leadership opportunities and long-term career development, we’d love to hear from you.