Penetration Tester

CBSbutler; England; On-site; GBP 85,000 - 100,000; Full time

Job summary

You will own engagements, mentor testers, and shape the growth of the Offensive Security capability while ensuring high-quality reports and actionable remediation guidance.

Qualifications

• Proven track record leading penetration testing engagements across complex environments.
• Experience with infrastructure, web apps, APIs, cloud, OT/ICS or wireless testing.
• Strong written risk communication and reporting skills.
• Ability to plan, scope, and quality assure engagements.
• Excellent client facing consulting and stakeholder management.
• Scripting experience (Python/PowerShell/Bash) or similar.
• Certified in OWASP/CREST or equivalent like OSCP/OSWE/OSRP.

Responsibilities

• Lead and deliver penetration testing engagements across multiple domains.
• Plan, scoping and manage engagements per CHECK requirements.
• Provide technical leadership and SME guidance on engagements.
• Quality assure findings, reports and testing outputs.
• Translate vulnerabilities into business risk and remediation steps.
• Mentor junior testers and CHECK Team Members.
• Help develop testing methodologies, tools and services.
• Engage with customers and senior stakeholders throughout the lifecycle.

Skills

Penetration testing leadership

CHECK Team leadership

Infrastructure pentest

Web apps pentest

APIs pentest

Cloud security testing

Python/PowerShell

Technical report writing

Client/stakeholder management

Security clearance

Tools

Security frameworks

MITRE ATT&CK

NCSC CAF/NIST/ISO27001

Job description

LEAD PENETRATION TESTER | CREST CHECK TEAM LEADER | UK NATIONAL SECURITY

Ready to lead from the front?

I'm working with an established UK technology and engineering organisation looking to bring an experienced CREST CHECK Team Leader (CTL) into its growing Offensive Security function.

This is an excellent opportunity for an established penetration testing professional who wants to combine hands on technical delivery with technical leadership along with the opportunity to influence the development of a wider security capability.

You'll be leading and delivering complex penetration testing engagements across defence, government and other high assurance environments, helping protect systems that support critical national security operations.

The opportunity:

You'll take ownership of:

• Leading and delivering penetration testing engagements across infrastructure, web applications, APIs, cloud, wireless and operational technology environments.
• Planning, scoping and managing engagements in line with NCSC CHECK requirements.
• Providing technical leadership and acting as a subject matter expert throughout engagements.
• Quality assuring technical findings, reports and testing outputs.
• Translating complex vulnerabilities into clear business risks and practical remediation recommendations.
• Mentoring junior penetration testers and CHECK Team Members.
• Helping develop testing methodologies, tools, standards and future service offerings.
• Engaging directly with customers and senior stakeholders throughout the testing lifecycle.

What we're looking for:

• Strong experience leading and delivering penetration testing engagements.
• Experience across one or more of infrastructure, web applications, APIs, cloud, wireless or OT/ICS.
• Excellent technical report writing and risk communication skills.
• Experience planning, scoping and quality assuring engagements.
• Strong client facing consulting and stakeholder management skills.
• Scripting experience with Python, PowerShell, Bash or similar.
• A good understanding of common security frameworks and standards.
• Existing SC or DV security clearance.
• OSCP, OSEP, OSWE, CRTO or equivalent certifications.
• AWS, Azure or GCP security testing.
• OT/ICS security testing.
• MITRE ATT&CK, NCSC CAF, NIST or ISO 27001.

Security:

You must be eligible to obtain SC clearance, potentially progressing to higher levels of National Security Vetting.

What's on offer?

• The opportunity to work on technically challenging engagements across Defence, Government and Critical National Infrastructure.
• A chance to influence the direction and development of an expanding Offensive Security capability.
• Professional development, specialist training and certification support.
• Dedicated opportunities for research and innovation.
• The ability to mentor and develop the next generation of penetration testing talent.

If you're a current CHECK Team Leader looking for a role where you can make an impact, I'd love to hear from you.

#PenetrationTesting #CREST #CHECK #CyberSecurity #OffensiveSecurity #NationalSecurity