Play a critical role in delivering high-quality penetration testing engagements across infrastructure, cloud, web, and mobile applications.
Identify and remediate security weaknesses.
Contribute to the development of methodologies and mentoring junior testers.
Work on varied, challenging projects in a supportive environment.

CHECK Team Member (CTM) status
Current UK Security Clearance.
At least 2+ years of penetration testing experience.
Strong experience with web application and network penetration testing methodologies.
In-depth knowledge of operating systems (Linux, Windows, Active Directory).
Familiarity with cloud environments and ability to perform cloud security reviews.
Proficiency with tools such as BurpSuite Pro, Nmap, Nessus, and Kali Linux.
Knowledge of scripting languages (Python, Shell, etc.).
CHECK Team Lead (CTL) status (Infrastructure or Applications)
Nice-to-Have.
Relevant certifications (OSCP, Cyber Scheme)
Nice-to-Have.
Experience with Hack the Box or Capture the Flag simulations
Nice-to-Have.

A discretionary annual performance bonus that rewards your impact and contribution to our success.
Flexible working arrangements and summer hours, because life isn’t 9 to 5, and balance matters.
A highly competitive pension scheme with generous employer contributions, private healthcare, and life assurance for peace of mind.
Employee Assistance Programme, mental health support, cycle-to-work scheme, and regular social events to keep our culture vibrant.
35 days holiday, enhanced maternity pay, and family-first policies so you can focus on what matters most.
From courses to certifications, we’ll invest in your development so you can keep growing and shaping what’s next.
Opportunities to volunteer, give back, and be part of initiatives that make Instil a truly inclusive and connected workplace.

Senior Penetration Tester

Key skills