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# Penetration Tester

- **Company:** Harnham
- **Location:** London, United Kingdom
- **Experience:** Expert
- **Salary:** £130,000 - £143,000
- **Contract:** Permanent contract
- **Skills:** Software System Penetration Testing, Complex Networks, Cyber Security, Computer Networks, Network Architecture, Operational Systems, Vulnerability Analysis
- **Published:** October 30, 2026
- **Apply:** https://www.reed.co.uk/jobs/penetration-tester/57504993

## About the Role

* Strong experience delivering infrastructure and network penetration testing engagements.
 * Proven capability in assessing complex network architectures and identifying exploitable weaknesses.
 * Experience managing the full penetration testing lifecycle independently, from scoping through to reporting.
 * Ability to communicate technical findings and recommendations clearly to a range of stakeholders.
 * Strong client-facing and report-writing skills.
 * Experience working across large, complex environments with multiple stakeholders.
 * Exposure to Operational Technology (OT) security testing would be advantageous.
 * Experience within telecommunications, retail, critical infrastructure, or similarly complex environments would be beneficial.
 * Comfortable collaborating with international teams across different regions and time zones., * Technical Presentations
 * Security Reporting
 * Stakeholder Management
 * Infrastructure & Network Penetration Testing
 * Network Architecture Assessments
 * End-to-End Penetration Testing
 * Vulnerability Identification & Exploitation
 * Enterprise Network Secur

## Description

This is an opportunity to join a growing in-house cyber security function that is continuing to expand its penetration testing capability across multiple business units. You'll take ownership of end-to-end testing engagements, working independently while helping shape the future direction of a mature and evolving security programme.
The Company
They are a large international organisation with a diverse portfolio of consumer-focused businesses operating across multiple regions. Over recent years, they have invested significantly in building internal cyber security capabilities, creating a consultancy-style function that supports a broad range of technology environments. Their security team works closely with stakeholders across Europe and Asia, delivering high-quality testing and security assurance services.
The Role and Deliverables

 * Lead and deliver end-to-end infrastructure and network penetration testing engagements.
 * Perform in-depth assessments of enterprise network architectures and identify security weaknesses beyond standard vulnerability scanning.
 * Conduct security testing across network boundaries and complex infrastructure environments.
 * Engage directly with stakeholders to scope testing activities and communicate findings.
 * Produce clear technical reports and present remediation recommendations to both technical and non-technical audiences.
 * Contribute to the ongoing development and maturity of the internal security testing capability.