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# Penetration Tester

- **Company:** Claranet Limited
- **Location:** London, UK
- **Salary:** £49,023.0
- **Contract:** Permanent contract
- **Skills:** C (Programming Language), Java (Programming Language), Software System Penetration Testing, C Sharp (Programming Language), C++ (Programming Language), Cyber Security, Perl (Programming Language), Mobile Application Software, Python (Programming Language), Network Architecture, Ruby, Web Applications, Scripting, Cloud Platform System
- **Published:** July 30, 2026
- **Apply:** https://www.adzuna.co.uk/jobs/details/5820963435

## About the Role

* Have a good understanding of web & mobile application and infrastructure testing and methodologies
 * Able to manually and proficiently exploit web application and network infrastructure vulnerabilities
 * Have a logical and time-conscious approach to report writing
 * Have a working knowledge of common programming languages such as C, C++, C#, Java
 * Have experience of at least one scripting language such as Ruby, Python or Perl

Essential Experience:

 * Delivering chargeable web app testing engagements
 * Providing remediation advice
 * Producing accurate technical reports
 * Working under pressure of deadlines and structuring workload accordingly
 * Problem-solving, helping others to understand complex ideas

Essential General:

 * Client facing, able to confidently and professionally represent the company
 * Must be self-motivated and able to work in an independent manner as well as part of a team
 * Excellent written and oral communications skills
 * Positive, collaborative and enthusiastic
 * Conducting penetration testing work out of normal office hours on occasion
 * Willing to travel to deliver onsite work as required
 * Appetite to shadow, train and develop to improve capabilities into all areas of security testing

In Addition, The Following Are Highly Desirable:

 * Security clearance (or eligibility for clearance)
 * CTM or CTL status
 * CISSP, CISA, CEH, OSCP or equivalent reputable information security certifications
 * Familiarity with testing cloud environments
 * Public speaking experience
 * Full UK driving license

## Description

* Undertaking web and mobile application testing and infrastructure testing engagements
 * Using the opportunities provided by the business to improve skills and capabilities into all areas of testing
 * Working with key clients providing bespoke consultancy, analysis and expertise
 * Collaborating with other Claranet Business Units on large client digital transformation projects
 * Assisting with pre/post sales activities as required
 * Encouraging a positive, proactive, collaborative and solution-oriented approach among colleagues
 * Communicating within Claranet and with clients, both orally and in writing
 * Contribute to the writing and publishing of whitepapers and advisories
 * Developing and delivering webinar content
 * Delivering targeted research and development in line with direction of the business
 * If not achieved already, working towards CREST qualifications; CPSA, CRT and CCT


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