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Penetration Tester

LorienLondon🇬🇧United KingdomPosted 21 Sept 2026

Quick Overview

Seniority
Mid Senior
Employment type
Full Time
Work mode
On Site
Location
London, United Kingdom
Penetration Testing

Job Description

PENETRATION TESTER/OFFENSIVE SECURITY CONSULTANT | DV ELIGIBLE | LONDON | 5 days a week on-site

Looking for your next penetration testing contract?

We're seeking experienced Penetration Testers/Offensive Security Consultants to help identify vulnerabilities across a complex technology landscape. This is an opportunity to work on meaningful security challenges, conducting real-world security assessments across infrastructure, cloud, applications and modern platforms.

Location: London
Contract: Long-term Contract
DV Clearance Eligibility Required

What You'll Be Doing

? Conducting penetration testing and vulnerability assessments across a range of environments.

? Simulating real-world attack scenarios to identify security weaknesses and risks.

? Producing high-quality technical reports with practical remediation recommendations.

? Working closely with security teams, engineers and system owners to improve security posture.

? Assessing infrastructure, applications and cloud environments against current threats.

? Communicating complex technical findings to both technical and non-technical stakeholders.

What We're Looking For

Strong experience in Penetration Testing and Offensive Security.

Expertise across one or more of the following areas:

* Windows Infrastructure
. Linux Infrastructure
. Network Security
. Cloud Environments
. Web Application Security
. Containerised Platforms
. Infrastructure as Code (IaC)
. CI/CD Security

Strong knowledge of Information Security principles and vulnerability management.

Experience communicating findings and working directly with technical stakeholders.

Desirable Certifications

OSCP, OSCE, OSEP

GPEN, GXPN, GWAPT, GRTP, GDSA

Crest or equivalent security certifications

DV Clearance Eligibility Requirements

. UK residency history with a clear and verifiable background.
. Strong financial integrity with no significant unresolved issues.
. Ability to successfully undergo enhanced security vetting and referencing.

Apply now if interested!

Guidant, Carbon60, Lorien & SRG - The Impellam Group Portfolio are acting as an Employment Business in relation to this vacancy.

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