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- Tasks: Conduct exciting penetration tests and lead client engagements to identify security vulnerabilities.
- Company: Join a leading offensive security consultancy with a dynamic team of experts.
- Benefits: Enjoy a competitive salary, remote work, travel expenses, and bonus for site visits.
- Other info: Flexible roles available with opportunities for career growth and clearance sponsorship.
- Why this job: Make a real impact in cybersecurity while working on diverse projects from anywhere.
- 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.
This role is fully remote with client site visits as required. No two weeks look the same.
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
Locations
Penetration Tester (CHECK / CREST) in Colchester, Essex 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 Colchester, Essex
✨Network Like a Pro
Get out there and connect with folks in the industry! Attend meetups, webinars, or even online forums. The more people you know, the better your chances of landing that Penetration Tester role.
✨Show Off Your Skills
Create a portfolio showcasing your penetration testing projects, CTFs, or any relevant labs you've completed. This is your chance to demonstrate your hands-on experience and passion for offensive security!
✨Ace the Interview
Prepare for technical interviews by brushing up on common vulnerability classes and exploitation techniques. Be ready to explain your thought process clearly, as communication is key when dealing with clients.
✨Apply Through Us!
Don't forget to apply through our website! We’ve got loads of opportunities waiting for talented Penetration Testers like you. Plus, we’re here to support you every step of the way!
We think you need these skills to ace Penetration Tester (CHECK / CREST) in Colchester, Essex
Some tips for your application 🫡
Tailor Your CV: Make sure your CV reflects the skills and experiences that match the Penetration Tester role. Highlight your hands-on experience with web applications, APIs, and infrastructure tests, and don’t forget to mention any relevant certifications like CHECK or CREST.
Craft a Compelling Cover Letter: Your cover letter is your chance to show us your passion for offensive security. Share specific examples of your work, how you’ve tackled challenges, and why you’re excited about joining our team. Keep it professional but let your personality shine through!
Showcase Your Reporting Skills: Since strong written reporting skills are key for this role, include samples of your reports if possible. We want to see how you communicate technical findings clearly and effectively, so make sure your writing is structured and easy to follow.
Apply Through Our Website: We encourage you to apply directly through our website. It’s the best way for us to receive your application and ensures you’re considered for the role. Plus, it gives you a chance to explore more about what we do at StudySmarter!
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, API, and infrastructure penetration testing. Be ready to discuss specific vulnerabilities like those in the OWASP Top 10 and share examples of how you've tackled them in past roles.
✨Client Communication is Key
Since this role involves client-facing engagements, practice explaining complex technical findings in simple terms. Think about how you would communicate high-risk issues to a non-technical audience and prepare some examples to demonstrate your communication skills.
✨Show Your Passion
Demonstrate your genuine interest in offensive security. Bring up any Capture The Flag (CTF) competitions, labs you've completed, or community involvement that showcases your enthusiasm and commitment to staying current in the field.
✨Prepare for Scenario Questions
Expect scenario-based questions that assess your problem-solving skills. Think through potential client scenarios and how you would approach them, from scoping to reporting. This will show your ability to take ownership of engagements and deliver quality results.