Principal Penetration Tester - CTL Infrastructure Cyber Security · Belfast

Instil
Belfast, Northern Ireland
11 months ago
Applications closed

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Posted
18 Jun 2025 (11 months ago)

At Vertical Structure (an Instil Company), we specialise in providing human-focused security and penetration testing services for web applications, cloud infrastructure and mobile applications.

The Role

We are looking for a CTL (Infrastructure) to join our dynamic team based in Belfast. As a Pen Tester, you will be part of the delivery team, conducting penetration tests and vulnerability assessments across a range of technologies and a wide range of customers including software, fintech, manufacturing, engineering, legal, and public sector. Your insights will be crucial in identifying security weaknesses and helping clients fortify their systems.

We offer varied, challenging work in a supportive environment where you will find yourself constantly evolving and learning, whilst studying towards further specialised certifications. If this sounds like you, we'd love to hear from you.

Location Requirements

This role is based in Belfast and may require some onsite work with clients. Therefore, candidates should be located in Northern Ireland.

Benefits

  • Competitive Salary & Annual Bonus
  • Hybrid Working
  • Flexible Working Hours
  • Summer Working Hours
  • 35 Days Holiday
  • Private Pension (8% Employer, 5% Employee)
  • Private Healthcare
  • Life Assurance
  • Cycle to Work Scheme

Day to Day

  • Co-ordinate and execute system/network level pen tests and ethical hacking exercises in client's Infrastructure/cloud, Web Applications and Mobile Applications.
  • Write detailed reports outlining vulnerabilities and providing tailored actionable recommendations.
  • Manage end-to-end testing, collaborating with clients during kick-off and discovery sessions, providing expert advice and follow up.
  • Stay current with the latest security threats, vulnerabilities, and trends.
  • Research offensive security techniques to assess and validate infrastructure and technologies, including cloud-based systems continuously incorporating new techniques into the team's methodology.
  • Automate repetitive tasks by developing scripts to streamline testing processes.
  • Mentor junior penetration testers and contribute to their professional development.
  • Play a key role in enhancing existing tools, methodologies, and reports.
  • Support pre-sales efforts by acting as a penetration testing subject-matter expert.
  • Communicate Security Vulnerabilities to both technical and non-technical stakeholders.
  • Contribute to thought leadership by writing blogs/white papers and/or speaking at conferences.

Need to Have

  • At least 5 years of experience in penetration testing.
  • UK Cyber Security Council Chartership status of Principal or above.
  • Subject matter expertise in web, mobile or network penetration testing with track record of end to end testing of complex systems.
  • Advanced knowledge of various web technologies, operating systems, particularly Linux, Windows, and Active Directory.
  • Knowledge of Scripting Languages e.g. Python, Shell Scripting etc.
  • Strong expertise with web application and network pen testing methodologies.
  • Proficiency in using penetration testing tools such as BurpSuite Pro, Nmap, Nessus, and Metasploit.
  • Experienced in using Kali Linux and the associated penetration testing tool suite.
  • Advanced completion of penetration testing simulations like Hack the Box or Capture the Flag or ideally one of the following certifications: CSTL/CCT, OSCP, OCWE, or relevant equivalent.
  • Excellent communication and technical report writing skills.
  • UK SC clearance.
  • Relevant security certifications (e.g. OSCP, CREST, Cyber Scheme).
  • Right to work in the UK (we are unable to provide VISA sponsorship).

Equality

Instil is an equal opportunity employer and values diversity at our company. We are committed to equality of opportunity for all staff. Applications from individuals are encouraged regardless of age, disability, gender reassignment, marriage and civil partnership, pregnancy and maternity, race, religion or belief, sex, and sexual orientation.


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