Security Tester | Contract (12 months+) | SC Clearance Required (Active/Lapsed) | Inside IR35

Security Tester | Contract (12 months+) | SC Clearance Required (Active/Lapsed) | Inside IR35 Location: Remote-first, UK Contract: Initial 12 months (potential to extend) Clearance: SC Clearance Required (Active/Lapsed)…

Inside IR35 IT
Pay rate £400 – £500/day
Contract type Contract
Posted 10 September 2026

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About this contract

Security Tester | Contract (12 months+) | SC Clearance Required (Active/Lapsed) | Inside IR35

Location: Remote-first, UK
Contract: Initial 12 months (potential to extend)
Clearance: SC Clearance Required (Active/Lapsed)

We are looking for an experienced Security Tester to support a major programme within a complex and highly regulated environment.

The successful consultant will bring strong hands-on security testing experience, with the ability to identify vulnerabilities, assess security controls and work closely with technical teams to ensure applications and systems meet required security standards.

You will work alongside engineering, development and wider testing teams, providing security testing expertise throughout the delivery lifecycle.

Key Responsibilities
Plan and execute security testing activities across applications, APIs and supporting systems.
Identify, assess and document security vulnerabilities and risks.
Perform hands-on security testing using appropriate manual and automated techniques.
Test application and system security controls against defined requirements.
Work closely with development and engineering teams to communicate findings and support remediation.
Retest vulnerabilities and security issues following remediation.
Produce clear security testing documentation and reports.
Support security assurance activities throughout the delivery lifecycle.
Work collaboratively with wider functional, integration and automation testing teams.Essential Experience
Strong hands-on experience within Security Testing / Application Security Testing.
Experience conducting security and vulnerability testing across enterprise applications.
Strong understanding of common application security vulnerabilities and OWASP principles.
Experience testing web applications and APIs.
Experience using relevant security testing and vulnerability assessment tools.
Ability to identify vulnerabilities, assess their potential impact and recommend remediation.
Experience producing clear security testing reports and documentation.
Experience working within complex enterprise environments.
Strong stakeholder engagement and communication skills.Desirable Experience
Experience working within defence, government or UK public-sector programmes.
Experience within highly regulated or security-critical environments.
Knowledge of secure software development and DevSecOps practices.
Experience working alongside Agile engineering and testing teams.
Relevant security testing certifications are advantageous but not essential

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