Security Penetration Tester

Reference: SPT_1781529747

As a Security Penetration Tester, you will be responsible for supporting the design, implementation, and maintenance of TVM (Threat & Vulnerability Management) solutions, controls and processes across the organisation. You will be liaising with Digital teams to ensure appropriate mitigation and remediation of vulnerabilities detected across our IT estate.

This role requires an understanding of TVM concepts, technologies, and best practices, as well as the ability to collaborate effectively with cross-functional teams. The ideal candidate will possess strong communication and will be committed to ensuring the highest level of security, compliance, and user experience.

Security Clearance: CTC (Counter Terrorist Check) clearance is essential. You must currently hold or be able to attain CTC clearance for this role.

What you'll be doing as a Security Penetration Tester

  • Help support and develop an internal penetration testing function.
  • Conduct network, application penetration testing, code and security reviews.
  • Identify and exploit vulnerabilities through proof-of-concept testing.
  • Support vulnerability management across the enterprise, ensuring that a framework for identification, categorisation and mitigation exists and is implemented and maintained.
  • Responsible for supporting the creation of the operating model for vulnerability management, that it is shared, agreed and operates effectively across the business.
  • Develop and maintain penetration testing documentation, policies, and procedures.
  • Integrate cyber security solutions (e.g. vulnerability scanning tools) with existing systems, applications, and infrastructure.
  • Evaluate and recommend technologies, tools, and vendors to meet business needs.
  • Investigate newly identified cyber security vulnerabilities and provide appropriate mitigation actions.
  • Liaise and coordinate with technology and business stakeholders in relation to cyber security patching and vulnerability management issues/actions.
  • Maintain a cyber threat assessment methodology, align to evolving industry standards and integrate into BAU and project-based business processes.
  • Support with proactive threat hunting for new and emerging cyber threats.
  • Develop and maintain dashboards with cyber security threat and vulnerability metrics.
  • Support compliance with relevant industry standards, regulations, and best practices, such as GDPR, NIS and ISO 27001.

What you should bring to the role

  • Strong knowledge of manual penetration testing techniques and confident with operating systems and tools such as Tenable, Burp Suite, Kalli Linux.
  • Exposure to remediating vulnerabilities and patch management in a complex business environment.
  • Experience in remediating cyber risks in the ever-changing digital estate.
  • Experience in a penetration testing enterprise environment.
  • Prepare detailed reports and the ability to present findings to key stakeholders.
  • Cyber security industry certification(s) such as CSTM/ CRT/ OSCP/CTL.
  • Understanding of different patching management techniques and approaches for different technology stacks (e.g. SaaS, IaaS, End-User Computing, Server Estate, etc.).
  • Knowledge of TVM concepts, technologies, and best practices, including OSINT tools, vulnerability assessment, threat modelling, etc

GCS is acting as an Employment Agency in relation to this vacancy.

£65,000.00 - £70,000.00
Per annum
GBP65000 - GBP70000 per annum
Added 15/06/2026
Reference: SPT_1781529747

Security Penetration Tester

Berkshire, United Kingdom Permanent Pen tester

Other similar jobs

Penetration Tester / Security Consultant)

Added 04/09/2026

Penetration Tester 📍 Remote | Europe 🕒 Full-Time Our client is looking for a Penetration Tester with 3+ years of experience to join a growing security consultancy team. Key Focus Areas:Web Application Security TestingAPI Security TestingAuthentication & Access Control ReviewsVulnerability Validation & ExploitationClient Reporting and Remediation Guidance Requirements:3+ years' hands-on penetration testing experienceStrong knowledge of OWASP Top 10 and API Security Top 10Experience with tools such as Burp Suite, Nmap, and NessusStrong report writing and client communication skills Highly preferred to have:CREST certifications (CRT/CCT), or OSCP+ and/or BSCPExperience with cloud security testingExposure to AI/LLM security assessments Join a collaborative team...

Learn more

Manual QA Tester - Web & Mobile Applications

Added 16/09/2026

Manual QA Tester - Web & Mobile Applications We're looking for a detail-oriented Manual QA Tester to help test web and mobile applications throughout the software development lifecycle. You'll work closely with Developers, Business Analysts, and Agile teams to make sure new functionality works as expected and existing functionality continues to perform reliably.ResponsibilitiesExecute manual test cases for new and existing application functionality.Perform regression, functional, exploratory, and ad-hoc testing.Build test cases designed to increase regression and feature coverage.Create testing data using SQL Server databases.Document testing results and report defects clearly.Work with development teams to reproduce, troubleshoot, and resolve issues.Review application logs...

Learn more

QA Tester

Added 16/09/2026

High-Level Role OverviewOur client is seeking an experienced Quality Assurance (QA) Professional to support software and mobile application testing initiatives. This individual will play a key role in ensuring product quality through effective test planning, execution, and validation across the software development lifecycle.Key ResponsibilitiesExecute manual testing for software and mobile applications.Develop, maintain, and execute comprehensive test cases and test scenarios.Identify, document, and track defects through resolution.Collaborate closely with developers, product managers, and Agile teams.Learn new products quickly and become a subject matter expert on functionality and user experience.Ensure releases meet quality standards and business requirements.Support API testing efforts and validate...

Learn more

Voice Core Tester

Added 31/08/2026

Voice Core TesterWe are seeking Voice Core Tester to support testing and analysis activities across VoLTE projects. The successful candidate will have strong testing experience, excellent analytical skills, and the ability to manage competing priorities while working to strict deadlines.​‌Please note: Visa sponsorship is not available for this position. Applicants must have the right to work in Ireland.Responsibilities The successful candidate will be responsible for:Analysing requirements and executing testing activitiesManaging test environments, configuring traces, and performing test executionInterpreting and analysing data to identify issues and troubleshoot problemsDeveloping and implementing appropriate configurations and solutionsMaintaining testing records and documentation, ensuring all updates...

Learn more

Software Tester

Added 28/08/2026

Software Tester (SC Cleared)We're looking for an experienced Software Tester with active SC Clearance to join a growing team delivering high-quality software solutions. You'll play a key role in ensuring applications meet functional and non-functional requirements through comprehensive testing, defect management, and collaboration with cross-functional teams.Key ResponsibilitiesCreate and execute test plans, test cases, and test scripts.Perform functional, regression, integration, and system testing.Identify, log, and track defects using tools such as Jira or Azure DevOps.Work closely with Developers, Business Analysts, and Product Owners to ensure quality throughout the development lifecycle.Support automated testing initiatives and identify opportunities to improve testing efficiency.Produce clear...

Learn more

Software Tester

Added 17/08/2026

Software Tester (SC Cleared)Drive quality. Accelerate delivery. Own automation. We're looking for a Software Tester who can build robust automated test solutions that boost efficiency, reduce manual effort, and ensure high‑quality software releases. What You'll DoBuild Automation Strategy - Identify what to automate, prioritise test cases, and shape a scalable automation approach.Develop Test Frameworks - Create and maintain automation frameworks using Selenium, Appium, TestNG, JUnit, or similar tools.Write & Execute Scripts - Build reliable, maintainable automated tests across platforms, devices, and environments.Integrate with CI/CD - Embed automated tests into pipelines using Jenkins, GitLab CI, Azure DevOps, etc.Manage Test Data -...

Learn more

Identity & Access Management (IAM) Test Analyst/Tester

Added 28/07/2026

Role OverviewWe are seeking an experienced Test Analyst/QA Tester with a background in Identity & Access Management (IAM) to test identity processing and user provisioning solutions across the identity lifecycle (Joiner, Mover, Leaver - JML).The successful candidate will be responsible for validating that user accounts, access rights, and entitlements are correctly provisioned, updated, and removed across multiple integrated systems, including HR systems, Active Directory (AD/LDAP), IAM platforms, and business applications.The role involves executing functional, integration, end-to-end, regression, and negative testing, validating identity data and business rules, performing SQL data validation, API testing using Postman, managing defects in Jira/ALM, and supporting...

Learn more

Automation Tester

Added 24/07/2026

Automation Tester Drive quality through automation.Are you passionate about software quality, automation, and delivering exceptional user experiences? We're seeking an Automation Tester / Software Development Engineer in Test (SDET) to help build robust testing frameworks and ensure the reliability of modern applications.This role offers the opportunity to work closely with developers, product teams, and engineering leaders to champion quality across the entire software development lifecycle.What You'll Be DoingDesigning, developing, and maintaining automated test frameworksCreating automated test suites for web, API, and backend servicesSupporting CI/CD pipelines and shift-left testing practicesPerforming regression, integration, and end-to-end testingIdentifying issues early and improving overall product...

Learn more

Software Tester

Added 02/07/2026

Software Tester (SC Cleared)Drive quality. Accelerate delivery. Own automation. We're looking for a Software Tester who can build robust automated test solutions that boost efficiency, reduce manual effort, and ensure high‑quality software releases. What You'll DoBuild Automation Strategy - Identify what to automate, prioritise test cases, and shape a scalable automation approach.Develop Test Frameworks - Create and maintain automation frameworks using Selenium, Appium, TestNG, JUnit, or similar tools.Write & Execute Scripts - Build reliable, maintainable automated tests across platforms, devices, and environments.Integrate with CI/CD - Embed automated tests into pipelines using Jenkins, GitLab CI, Azure DevOps, etc.Manage Test Data -...

Learn more

Head of Cyber Security

Added 16/09/2026

Head of Cybersecurity The OpportunityWe are seeking an experienced Head of Cybersecurity to join a senior leadership team within a large, complex organisation operating in a highly regulated and rapidly evolving digital environment. The successful candidate will work closely with senior stakeholders across a broad range of organisations and industries, helping shape strategic approaches to emerging cybersecurity, technology and resilience requirements.The RoleThe Head of Cybersecurity will lead and develop a multidisciplinary team of experienced engagement and policy professionals. The role will involve significant engagement with senior stakeholders across industry, technology, public and private sector organisations, professional networks and other key...

Learn more

Cyber Security Automation Engineer

Added 15/09/2026

Role- Senior Security Automation EngineerType- ContractDuration- 12+ monthsLocation- Mt. Laurel, NJOverviewSeeking a Senior Security Automation Engineer to build AI-driven security automation solutions within a Cyber Security Operations Center (CSOC). This is a hands-on engineering role focused on developing intelligent agents and automated workflows that improve threat detection, investigations, and incident response.Key ResponsibilitiesDesign, develop, deploy, and maintain production-grade security automation and AI-powered workflows.Build AI agents capable of accessing security data, using tools, maintaining context, and executing multi-step tasks.Automate processes across:Threat IntelligenceThreat HuntingDetection EngineeringSecurity InvestigationsIncident ResponseSecurity Data AnalysisApply advanced AI techniques including:Tool CallingRetrieval-Augmented Generation (RAG)Structured GenerationPlanning & ReflectionVerificationModel RoutingMulti-Agent CoordinationDesign memory, context...

Learn more

Automation Security Engineer

Added 14/09/2026

This position is ideal for an engineer who enjoys solving complex problems and building new capabilities from the ground up. The role goes beyond traditional security scripting, SOAR configuration, or test automation. You will help develop intelligent systems that can augment and automate the work performed by threat intelligence, threat hunting, detection engineering, investigation, and incident response teams. Key ResponsibilitiesDesign, develop, test, deploy, and operate production-grade security automation and AI-driven workflows.Build intelligent agents capable of securely accessing security data, invoking approved tools, maintaining context, and executing multi-step workflows.Develop automation that can assist with:Threat intelligenceThreat huntingDetection engineeringSecurity investigationsIncident responseSecurity data analysisApply...

Learn more

Security Automation Engineer

Added 09/09/2026

Key ResponsibilitiesDesign, develop, test, deploy, and operate production-grade security automation and AI-driven workflows.Build intelligent agents capable of securely accessing security data, invoking approved tools, maintaining context, and executing multi-step workflows.Develop automation that can assist with:Threat intelligenceThreat huntingDetection engineeringSecurity investigationsIncident responseSecurity data analysisApply modern AI and automation techniques, including:Tool callingRetrieval-augmented generation (RAG)Structured generationPlanningReflectionVerificationModel routingMulti-agent coordinationDesign mechanisms for memory, context management, task recovery, escalation, and human approval.Build automation designed to reduce operational noise and false positives while improving the speed and consistency of security response.Develop appropriate security controls and guardrails around AI agents and automated workflows.Create evaluation and testing strategies to measure...

Learn more

Security Engineer

Added 09/09/2026

Key ResponsibilitiesDesign, develop, test, deploy, and operate production-grade security automation and AI-driven workflows.Build intelligent agents capable of securely accessing security data, invoking approved tools, maintaining context, and executing multi-step workflows.Develop automation that can assist with:Threat intelligenceThreat huntingDetection engineeringSecurity investigationsIncident responseSecurity data analysisApply modern AI and automation techniques, including:Tool callingRetrieval-augmented generation (RAG)Structured generationPlanningReflectionVerificationModel routingMulti-agent coordinationDesign mechanisms for memory, context management, task recovery, escalation, and human approval.Build automation designed to reduce operational noise and false positives while improving the speed and consistency of security response.Develop appropriate security controls and guardrails around AI agents and automated workflows.Create evaluation and testing strategies to measure...

Learn more

Security Architect

Added 08/09/2026

Job DescriptionJob TitleSecurity Architect (12-Month Fixed-Term Contract)LocationHybrid - Warrington, EnglandContract12-Month Fixed-Term Contract (FTC)Role OverviewWe are seeking an experienced Security Architect to join an Enterprise Security team, responsible for ensuring the design and delivery of secure technology solutions across a large-scale transformation programme.The successful candidate will produce high-level and low-level security designs for multiple high-impact initiatives, ensuring solutions are secure by design, compliant with security standards, and aligned with business objectives.Working closely with Solution Architects, Project Managers, Business Analysts, and technical stakeholders, you will provide expert security guidance throughout the project lifecycle-from initial solution design through to implementation and deployment into...

Learn more
At least 8 characters, 1 uppercase, 1 lowercase and 1 special character or number
Your file must be a doc, docx or pdf. No larger than 5MB.