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- Tasks: Conduct penetration tests on web apps, APIs, and infrastructure while leading client engagements.
- Company: Join a top UK consultancy focused on offensive security with a dynamic team.
- Benefits: Enjoy a competitive salary, remote work, travel expenses, and clearance sponsorship.
- Other info: Flexible roles available with excellent career growth and mentorship opportunities.
- Why this job: Make a real impact in cybersecurity while working with cutting-edge technologies.
- Qualifications: Experience in penetration testing and strong communication skills are essential.
The predicted salary is between 55000 - 90000 £ per year.
Location: Fully Remote, UK (with client site visits as required)
Salary: £55,000 - £90,000 DOE + expenses + overnight bonus for site work
Type: Permanent, Full-Time
Summary: We are looking for experienced Penetration Testers to join one of the UK's larger dedicated offensive security practices. With a team of around 70 testers split across CHECK and CREST work, this is a well-established consultancy delivering high-quality assessments across a broad client base, with genuine variety in engagement type, sector, and technical depth. The team is structured across two streams, more commercially-driven engagements through CREST, and deeper, security-led work through CHECK, so there's a clear path whichever direction you want to lean. Multiple roles are available across mid and senior levels, and the company is flexible on starting clearance level.
Key Responsibilities:
- Deliver web application, API, and infrastructure penetration tests, taking ownership of engagements end-to-end from scoping through to final report delivery.
- Lead client-facing engagements, communicating high-risk findings as they are identified to support swift remediation.
- Produce clear, professional reports tailored to client-specific context and business risk.
- Support broader offensive security activities including red and purple team engagements, phishing simulations, and assumed-breach style assessments where relevant.
- Contribute to internal QA, mentor more junior consultants, and support report quality across the team.
- Stay up to date with the evolving threat landscape and contribute to internal R&D, tooling, and knowledge sharing.
Requirements:
- CHECK Team Member (CTM), CHECK Team Leader (CTL), CREST Registered Tester (CRT), or CREST Certified Tester (CCT) qualified, or actively progressing along either pathway at a senior level.
- Hands-on experience delivering web application, API, and/or infrastructure penetration tests in a professional consultancy setting.
- Strong understanding of common vulnerability classes (e.g. OWASP Top 10), exploitation techniques, and remediation guidance.
- Confident client-facing communication skills, with the ability to explain technical findings to both technical and non-technical audiences.
- Strong written reporting skills, with the ability to produce clear, well-structured deliverables.
- A genuine passion for offensive security, demonstrated through CTFs, labs (e.g. Hack The Box, TryHackMe), research, certifications, or community involvement.
Clearance: Clearance requirements vary by role, some do not require any clearance, others are looking for SC or DV. The company will put successful candidates through the relevant clearance process where required, so existing clearance is welcomed but not essential across the board.
Benefits:
- Salary: £55,000 - £90,000, depending on experience, certifications and clearance level
- Fully remote working
- Overnight bonus for client site visits
- Travel and expenses covered for client work
- Clearance sponsorship (SC / DV) where required for the role
- Company pension scheme
Penetration Tester (CHECK / CREST) in London employer: Oscar Associates (UK) Limited
Contact Detail:
Oscar Associates (UK) Limited Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Penetration Tester (CHECK / CREST) in London
✨Tip Number 1
Network like a pro! Reach out to fellow penetration testers and industry professionals on LinkedIn or at local meetups. Building connections can lead to job opportunities that aren’t even advertised yet.
✨Tip Number 2
Show off your skills! Create a portfolio showcasing your penetration testing projects, CTF achievements, or any relevant research. This gives potential employers a taste of what you can do beyond just a CV.
✨Tip Number 3
Prepare for interviews by brushing up on your client-facing communication skills. Practice explaining complex technical concepts in simple terms, as you'll need to convey findings to both tech-savvy and non-tech audiences.
✨Tip Number 4
Don’t forget to apply through our website! We’ve got multiple roles available, and applying directly can give you a better chance of landing that dream job with us. Plus, we love seeing candidates who are proactive!
We think you need these skills to ace Penetration Tester (CHECK / CREST) in London
Some tips for your application 🫡
Tailor Your CV: Make sure your CV is tailored to the Penetration Tester role. Highlight your relevant experience, especially in web application and API testing, and don’t forget to mention any certifications like CHECK or CREST that you have.
Show Off Your Skills: In your cover letter, showcase your hands-on experience with penetration testing. Talk about specific projects or challenges you've tackled, and how you communicated findings to clients. We love seeing your passion for offensive security!
Be Clear and Concise: When writing your application, keep it clear and concise. Use professional language but make sure it’s easy to read. We appreciate well-structured reports, so show us you can do the same in your application!
Apply Through Our Website: Don’t forget to apply through our website! It’s the best way for us to receive your application and ensures you’re considered for the role. We can’t wait to see what you bring to the table!
How to prepare for a job interview at Oscar Associates (UK) Limited
✨Know Your Stuff
Make sure you brush up on your technical skills, especially around web application and infrastructure penetration testing. Familiarise yourself with the OWASP Top 10 and be ready to discuss your hands-on experience with various tools and techniques.
✨Tailor Your Communication
Since you'll be leading client-facing engagements, practice explaining complex technical findings in a way that non-technical stakeholders can understand. This will show your ability to bridge the gap between technical and business perspectives.
✨Show Your Passion
Demonstrate your genuine interest in offensive security by sharing your experiences with CTFs, labs, or any community involvement. This not only highlights your skills but also shows that you're committed to staying updated with the evolving threat landscape.
✨Prepare for Scenario Questions
Expect scenario-based questions during the interview. Think about how you would handle specific penetration testing situations, from scoping to reporting. Being able to articulate your thought process will impress the interviewers.