Penetration Tester (Infrastructure)

JR United Kingdom; London; On-site; GBP 50,000 - 80,000; Full time

Job summary

A leading company in digital security seeks an experienced Infrastructure Penetration Tester for a hands-on role. You'll conduct critical assessments in sensitive client environments, produce detailed reports, and contribute to internal methodologies. If you're motivated by impactful work and thrive in challenging scenarios, this position offers great autonomy and the chance to work with a high-performing team.

Qualifications

• At least 4 years’ experience in infrastructure penetration testing.
• Strong knowledge of Active Directory exploitation techniques.
• Experience with legacy systems and unpatched software.

Responsibilities

• Conduct internal infrastructure and Active Directory penetration tests.
• Produce clear and concise reports for various audiences.
• Build trusted relationships with clients in consultancy.

Skills

Active Directory exploitation techniques

Command-line skills (Windows and Linux)

Infrastructure exploitation tools

Python scripting

Job description

Social network you want to login/join with:

Penetration Tester (Infrastructure), london

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Client:

Anson McCade

Location:

london, United Kingdom

Job Category:

Other

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EU work permit required:

Yes

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Job Views:

2

Posted:

24.06.2025

Expiry Date:

08.08.2025

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Job Description:

Note: To be eligible for this role, you must be eligible for UK Security Clearance (SC).

A high-performing digital security team is looking for an experienced Infrastructure Penetration Tester to join them in delivering critical assessments across complex and sensitive client environments.

This is a hands-on internal testing role, not web application focused, where you'll be expected to work independently and navigate challenging systems with confidence.

This role is suited to testers who thrive in technically demanding scenarios, want autonomy, and are motivated by work with real-world impact.

Key Responsibilities

• Conduct internal infrastructure and Active Directory penetration tests in live production environments
• Produce clear, concise reports tailored to both technical and non-technical audiences
• Build trusted relationships with clients in a consultancy-facing capacity
• Work within a small, high-trust team on sensitive engagements
• Contribute to the evolution of internal tooling and testing methodologies
• Operate effectively in environments with limited documentation or predefined processes

Essential Experience and Skills

• At least 4 years’ experience in infrastructure penetration testing
• Strong knowledge of Active Directory exploitation techniques (privilege escalation, lateral movement, etc.)
• Strong command-line skills across Windows and Linux systems
• Ability to work through legacy systems, unpatched software, and environments with technical debt
• Python scripting or automation experience
• Understanding of Operational Technology (OT) networks
• Familiarity with internal infrastructure exploitation tools

Certifications (preferred but not essential):

• CREST CTM, CTL, CSTM or Cyber Scheme Practitioner
• OSCP (current or lapsed)

If you’re an experienced infrastructure penetration tester looking for meaningful work, we want to hear from you.