Ideas | People | Trust

We’re BDO. An accountancy and business advisory firm, providing the advice and solutions entrepreneurial organisations need to navigate today’s changing world.

We work with the companies that are Britain’s economic engine – ambitious, entrepreneurially-spirited and high growth businesses that fuel the economy - and directly advise the owners and management teams that lead them.

We’ll broaden your horizons

At our core, we believe that growth comes from exposure to diverse challenges. In this role, you'll have the opportunity to work across a wide range of engagements, thanks to the trust and scale of our clients.

You will get hands-on experience with web application and API testing, Wireless assessments, Internal infrastructure tests, Mobile App security, Red and Purple team operations, Physical intrusion testing, hardware analysis, and more. No two projects are quite the same, and that’s exactly how we like it. This variety allows our team to explore different domains, deepen existing strengths, and discover new areas of interest, all while solving real-world problems in live environments. Whether you're still shaping your focus or refining an existing specialty, you'll have space here to grow meaningfully.

Manage risk for our clients to make them stronger for the future.

Our Digital Services are designed to enable organisations to leverage our innovative methodologies, technology, and highly experienced professionals to manage their business risks most effectively. Working at BDO offers curious-minded people excellent exposure to all aspects of business strategy, operations and more.

We’re a dynamic team of internal auditors, accountants, technology, and business transformation experts with disciplines in finance, risk, projects and change, cyber and digital, amongst others.

Our extensive network and depth of experience mean we work in a highly client-centric way, focused on providing a collaborative, tailor-made advisory service. Our team helps clients manage their business-critical threats, such as cyber events, and build resilient businesses capable of responding to internal and external events which may interrupt their operations. Being known for exceptional client service in our chosen markets, we put innovation and agility at the heart of everything we do.

This is your chance to join a fast-paced, growing team and help shape the future of Digital at BDO.

We’ll help you succeed

Leading organisations trust us because of the quality of our advice. That quality grows from a thorough understanding of their business, and that understanding comes from working closely with them and building long-lasting relationships.

You’ll be someone who is both comfortable working proactively and managing your own tasks, as well as confident collaborating with others and communicating regularly with senior managers, directors, and BDO’s partners to help businesses effectively. You’ll be encouraged to identify and draw attention to opportunities for enhancing our delivery and providing additional services to organisations we work with.

We are seeking a highly skilled and experienced Senior Offensive Security penetration tester to join our dynamic team. This role involves conducting sophisticated penetration testing and red team engagements across various client systems and applications. The successful candidate will be instrumental in identifying vulnerabilities, enhancing client security postures, and leading initiatives to develop cutting-edge penetration testing methodologies and tools. Clients across industries and geographies, staying at the forefront of knowledge of the threat landscape, cyber defence best practices and regulatory expectations. 

Requirements:

•             Strict Requirement: Strong certification in penetration testing such as OSCP (Offensive Security Certified Professional), CTM (Check Team Member), CRT (CREST Registered Tester) and OSWA (Offensive Security Web Attacks) or even better if you have Advanced certifications such as OSEP(OffSec Experience Penetration Tester), CCSAM (CREST Certified Simulated Attack Manager) and CTL (Check Team Leader).

•             Solid experience in offensive security—whether through professional penetration testing, red teaming, bug bounty work, capture-the-flag competitions, or personal research projects.

•             Proven ability to deliver impactful client engagements, demonstrating both technical depth and a practical understanding of risk.

•             Deep knowledge of network protocols, different services, operating systems, different applications and how to break them.

•             Proficiency in tools such as Metasploit, Burp Suite or other proxies such as Caido or Zap, Nessus, CobaltStrike or other C2 frameworks, etc. Bonus points for building your own tools, contributing to community projects, or chaining techniques creatively.

•             Excellent problem-solving skills and a passion for ethical hacking that is persistent, curious, and know how to pivot when things do not go as planned.

•             Experience coding and scripting custom tools in Python, Bash, PowerShell, or anything else that gets the job done.

•             Ability to communicate technical findings clearly to both technical and non-technical stakeholders.

Be yourself

It's at the core of the company's and team's vision. You’ll be able to truly be yourself; we’ll recognise and value you for who you are and celebrate and reward your contributions to the business. We’re committed to agile working, and we offer every colleague the opportunity to work in ways that suits them, their teams, and the tasks at hand.

At BDO, we’re committed to helping you achieve your personal and professional goals. We provide structured development frameworks, resources, and mentorship to support your growth—whether you're looking to deepen a specific skillset or broaden your expertise across domains.

We’ll align your client engagements with your learning objectives, giving you the chance to apply new skills, explore areas of interest, and gain practical experience. You won’t be navigating this alone—our team culture emphasizes peer support, collaboration, and knowledge sharing on every project.

We’re in it together

Mutual support and respect are one of BDO’s core values and we’re proud of our distinctive, people-centred culture. From informal success conversations to formal mentoring and coaching, we’ll support you at every stage in your career, whatever your personal and professional needs.

Our agile working framework helps us stay connected, bringing teams together where and when it counts so they can share ideas and help one another. At BDO, you’ll always have access to the people and resources you need to do your best work.

We know that collaboration is the key to creating value for the companies we work with and satisfying experiences for our colleagues, so we’ve invested in state-of-the-art collaboration spaces in our offices. BDO’s people represent a wealth of knowledge and expertise, and we’ll encourage you to build your network, work alongside others, and share your skills and experiences. With a range of multidisciplinary events and dedicated resources, you’ll never stop learning at BDO.

We’re looking forward to the future

At BDO, we help entrepreneurial businesses to succeed, fueling the UK economy. Our success is powered by our people, which is why we’re always finding new ways to invest in you. Across the UK thousands of unique minds continue to come together to help companies we work with to achieve their ambitions.

We’ve got a clear purpose, and we’re confident in our future, because we’re adapting and evolving to build on our strengths, ensuring we continue to find the right combination of global reach, integrity and expertise. We shape the future together with openness and clarity, because we believe in empowering people to think creatively about how we can do things better.

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