Security Threat Hunting Specialist in London

Our Purpose Mastercard powers economies and empowers people in 200+ countries and territories worldwide. Together with our customers, we’re helping build a sustainable economy where everyone can prosper. We support a wide range of digital payments choices, making transactions secure, simple, smart and accessible. Our technology and innovation, partnerships and networks combine to deliver a unique set of products and services that help people, businesses and governments realize their greatest potential. Title and Summary Lead Threat Intelligence Analyst Overview This is an exciting position for a Lead Threat Intelligence Analyst to join Vocalink’s dedicated Threat Intelligence function. You will be play an integral leading role in the Vocalink Threat Intelligence Team, working closely with the SOC and internal security teams to deliver actionable intelligence. You will support a diverse range of customers and contribute to key initiatives such as threat hunting, vulnerability management, and insider threat detection. Collaboration is at the heart of this position. You will work alongside Mastercard’s global threat intelligence capabilities and engage proactively with a wide network of stakeholders, including vendors, industry groups, our customers, and government organisations. This is a unique chance to help shape and grow a fast-evolving threat intelligence capability that serves Vocalink and its customers. If you are passionate about cyber security and eager to make an impact, this role offers an exciting platform to develop your leadership expertise and to help to grow and mature a threat intelligence function in a critical national infrastructure provider. Role Lead the day-to-day operations of the threat intelligence function within the Vocalink Security Operations Cent

🚀 About WRITER WRITER is where the world's leading enterprises orchestrate AI-powered work. Our vision is to expand human capacity through superintelligence. And we're proving it's possible – through powerful, trustworthy AI that unites IT and business teams together to unlock enterprise-wide transformation. With WRITER's end-to-end platform, hundreds of companies like Mars, Marriott, Uber, and Vanguard are building and deploying AI agents that are grounded in their company's data and fueled by WRITER's enterprise-grade LLMs. Valued at $1.9B and backed by industry-leading investors including Premji Invest, Radical Ventures, and ICONIQ Growth, WRITER is rapidly cementing its position as the leader in enterprise generative AI. Founded in 2020 with office hubs in San Francisco, New York City, Seattle, Austin, Chicago, and London, our team thinks big and moves fast, and we're looking for smart, hardworking builders and scalers to join us on our journey to create a better future of work with AI. 📐 About the role Join WRITER's security team as a staff detection and response engineer and help protect the AI infrastructure that's transforming how the world works. You'll build sophisticated detection systems that identify attacks targeting our AI platform, training data, and model deployments while creating automated response capabilities that scale with our explosive growth. This isn't just traditional security work – you're defending cutting-edge AI/AGI systems against adversaries who are evolving their tactics as fast as AI itself advances. This role combines hands-on security engineering with strategic thinking to stay ahead of novel threats that don't exist in textbooks yet. You'll be the operational arm of our security function, translating threat intelligence into real-time detections, coordinating incident response across multiple teams, and hunting for sophisticated attacks across GPU clusters and distributed training environments. If you're excited by the challen

🚀 About WRITER WRITER is where the world's leading enterprises orchestrate AI-powered work. Our vision is to expand human capacity through superintelligence. And we're proving it's possible – through powerful, trustworthy AI that unites IT and business teams together to unlock enterprise-wide transformation. With WRITER's end-to-end platform, hundreds of companies like Mars, Marriott, Uber, and Vanguard are building and deploying AI agents that are grounded in their company's data and fueled by WRITER's enterprise-grade LLMs. Valued at $1.9B and backed by industry-leading investors including Premji Invest, Radical Ventures, and ICONIQ Growth, WRITER is rapidly cementing its position as the leader in enterprise generative AI. Founded in 2020 with office hubs in San Francisco, New York City, Seattle, Austin, Chicago, and London, our team thinks big and moves fast, and we're looking for smart, hardworking builders and scalers to join us on our journey to create a better future of work with AI. 📐 About the role Join WRITER's security team as a staff detection and response engineer and help protect the AI infrastructure that's transforming how the world works. You'll build sophisticated detection systems that identify attacks targeting our AI platform, training data, and model deployments while creating automated response capabilities that scale with our explosive growth. This isn't just traditional security work – you're defending cutting-edge AI/AGI systems against adversaries who are evolving their tactics as fast as AI itself advances. This role combines hands-on security engineering with strategic thinking to stay ahead of novel threats that don't exist in textbooks yet. You'll be the operational arm of our security function, translating threat intelligence into real-time detections, coordinating incident response across multiple teams, and hunting for sophisticated attacks across GPU clusters and distributed training environments. If you're excited by the challen

About the Team Security is at the foundation of OpenAI’s mission to ensure that artificial general intelligence benefits all of humanity. The Threat Intelligence team protects OpenAI’s technology, people, research, and infrastructure by proactively identifying and disrupting adversaries who seek to compromise our systems or misuse our models. We investigate sophisticated threats, build tooling to scale and augment analysis, and deliver intelligence that shapes security strategy and equips leadership with timely, risk-aware insights. We combine technical depth, investigative rigor, and strong cross-functional partnerships to uncover threats and drive impact across OpenAI’s security and research organizations. About the Role As a Technical Threat Investigator at OpenAI, you will help protect the company from sophisticated adversaries targeting OpenAI and the broader ecosystem, as well as those attempting to misuse our models in support of cyber operations. This is a deeply investigative role. You will independently conduct complex, end-to-end investigations into capable threat actors to understand their behavior, infrastructure, emerging techniques, and how AI is integrated into their workflows. You’ll use these insights to proactively identify malicious activity and drive detection, disruption, enforcement, and safety improvements across the company. You’ll translate your investigative findings into durable solutions that scale impact. You’ll build and own lightweight tooling, automate where it matters, and create AI-assisted workflows to make investigations faster, more repeatable, and more effective over time. In this role, you will: Conduct deep, end-to-end investigations into sophisticated threat actors interacting with OpenAI’s models, products, and broader ecosystem. Think like an adversary — model attacker behavior, anticipate misuse patterns, and proactively hunt for, identify, and disrupt malicious activity. Leverage internal telemetry, OSINT, vendor data, a

🚀 About WRITER WRITER is where the world's leading enterprises orchestrate AI-powered work. Our vision is to expand human capacity through superintelligence. And we're proving it's possible – through powerful, trustworthy AI that unites IT and business teams together to unlock enterprise-wide transformation. With WRITER's end-to-end platform, hundreds of companies like Mars, Marriott, Uber, and Vanguard are building and deploying AI agents that are grounded in their company's data and fueled by WRITER's enterprise-grade LLMs. Valued at $1.9B and backed by industry-leading investors including Premji Invest, Radical Ventures, and ICONIQ Growth, WRITER is rapidly cementing its position as the leader in enterprise generative AI. Founded in 2020 with office hubs in San Francisco, New York City, Seattle, Austin, Chicago, and London, our team thinks big and moves fast, and we're looking for smart, hardworking builders and scalers to join us on our journey to create a better future of work with AI. 📐 About the role This is where security meets innovation at enterprise scale. As a security engineer, applications at WRITER, you'll be building the security foundations that protect the AI systems powering some of the world's most recognizable brands. You'll work at the intersection of application security, AI infrastructure, and developer enablement—partnering with engineering teams to embed security into every line of code while ensuring our platform remains both powerful and trustworthy. The opportunity is massive: you'll help define how enterprise AI applications are secured, from threat modeling our LLM architectures to building automated security controls that scale across our growing platform. This isn't about saying "no"—it's about finding creative ways to say "yes, and here's how we do it securely." You'll tackle challenges that most security engineers never encounter: securing AI agents, protecting training data pipelines, and designing controls for systems that didn

🚀 About WRITER WRITER is where the world's leading enterprises orchestrate AI-powered work. Our vision is to expand human capacity through superintelligence. And we're proving it's possible – through powerful, trustworthy AI that unites IT and business teams together to unlock enterprise-wide transformation. With WRITER's end-to-end platform, hundreds of companies like Mars, Marriott, Uber, and Vanguard are building and deploying AI agents that are grounded in their company's data and fueled by WRITER's enterprise-grade LLMs. Valued at $1.9B and backed by industry-leading investors including Premji Invest, Radical Ventures, and ICONIQ Growth, WRITER is rapidly cementing its position as the leader in enterprise generative AI. Founded in 2020 with office hubs in San Francisco, New York City, Seattle, Austin, Chicago, and London, our team thinks big and moves fast, and we're looking for smart, hardworking builders and scalers to join us on our journey to create a better future of work with AI. 📐 About the role This is where security meets innovation at enterprise scale. As a security engineer, applications at WRITER, you'll be building the security foundations that protect the AI systems powering some of the world's most recognizable brands. You'll work at the intersection of application security, AI infrastructure, and developer enablement—partnering with engineering teams to embed security into every line of code while ensuring our platform remains both powerful and trustworthy. The opportunity is massive: you'll help define how enterprise AI applications are secured, from threat modeling our LLM architectures to building automated security controls that scale across our growing platform. This isn't about saying "no"—it's about finding creative ways to say "yes, and here's how we do it securely." You'll tackle challenges that most security engineers never encounter: securing AI agents, protecting training data pipelines, and designing controls for systems that didn

About the Team Security is at the foundation of OpenAI’s mission to ensure that artificial general intelligence benefits all of humanity. The Security team protects OpenAI’s technology, people, and products. We are technical in what we build but are operational in how we do our work, and are committed to supporting all products and research at OpenAI. Our Security team tenets include: prioritizing for impact, enabling researchers, preparing for future transformative technologies, and engaging a robust security culture. About the Role As a Security Engineer on Detection & Response, you’ll help protect OpenAI’s most sensitive assets– including our intellectual property, customer data, and the infrastructure that supports them– by building and operating the systems we use to detect suspicious activity and respond effectively when it matters. You’ll work across endpoints, identity, cloud, hyperscale compute infrastructure, and datacenter-adjacent layers, partnering closely with security teams and infrastructure owners to define the telemetry and response requirements we need and building tooling and automation where it delivers the most leverage. In this role, you will: Build and evolve Detection & Response capabilities across OpenAI’s infrastructure, products, and research environments, with an emphasis on high-signal detection and reliable operational response. Engineer detection pipelines and tooling: develop rule lifecycle management, measurement/quality loops (coverage, precision, latency), tuning processes, and safe rollout patterns. Automate response and investigations by building workflows that reduce toil (triage, enrichment, containment, evidence capture) and improve time-to-understand/time-to-contain. Partner with other Security teams and system/infrastructure owners across the company to ensure new systems ship with the right telemetry, threat models, and response playbooks from day one. Define D&R requirements and drive visibility across endpoin

At Rockstar Games, we create world-class entertainment experiences. Become part of a team working on some of the most rewarding, large-scale creative projects to be found in any entertainment medium - all within an inclusive, highly-motivated environment where you can learn and collaborate with some of the most talented people in the industry. Rockstar is on the lookout for a passionate a Senior Manager to lead and develop our Game Security team. In this dynamic role you’ll be committed to ensuring our games and services remain secure and enjoyable by protecting against cheaters, vulnerabilities, and exploits. You’ll be responsible for designing and implementing processes to continuously strengthen our game security programme, mitigating threats to the player experience while evolving the efficacy of our enforcement and operations teams. This is a full-time, permanent and in-office position based in Rockstar’s unique game development studio in the heart of London. WHAT WE DO The Game Security team is responsible for protecting our players, our games, and intellectual property from malicious actors. We work across multiple disciplines to detect, deter, and disrupt threats impacting the player experience. We work closely with other teams to enforce, support, and improve security solutions. RESPONSIBILITIES Leverage extensive subject matter expertise to develop and support anti-cheat initiatives and protect the integrity of our live service titles. Lead, mentor, and manage a talented and cross functional team engaged in day-to-day anti-cheat operations for our online titles. Set team priorities, allocate resources effectively, and plan for future growth to meet organisational objectives. Establish and standardise operational processes, tools, and best practices. Contribute to the development and monitoring of key risk and performance indicators in partnership with our analytics and i

Who are we? Cohere is the leading security-first enterprise AI company. We build cutting-edge foundation AI models and end-to-end products that are designed to solve real-world business problems. We’re training and deploying frontier models for enterprises who are building AI systems. We believe that our work is instrumental to the widespread adoption of AI and we are looking for folks that want to be part of that. We obsess over what we build. Each one of us is responsible for contributing to increasing the capabilities of our models and the value they drive for our customers. Cohere is a team of researchers, engineers, designers, and more, who are all passionate about their craft. We are a global technology company headquartered in Toronto with key offices in London, New York City, San Francisco, Montreal, Paris, Berlin and Seoul. Join us! As a Senior Security Operations Engineer you will: Serve as trusted advisor to team’s leadership and partner teams by clearly articulating business risks associated with security issues Harden our cloud-native environments (AWS, OCI, GCP) by introducing secure by default designs and features into network, tooling, and processes Own and drive resolutions for enabling engineers to design, build, and use infrastructure securely at scale by deploying secure architectures using infrastructure-as-code and reusable code libraries Manage IAM / RBAC for cloud infrastructure, and partner with IT on streamling authentication/authorization to ensure unified access control across the board Deploy and operationalize some of the security services and tools (eg: SIEM, SOAR, domain monitoring, endpoint tooling, cloud security tooling) Respond to security incidents and harden environments post-incidents. Support control monitoring and remediation for compliance initiatives Gather and analyze security metrics to address security issues with cross-team dependencies Be a problem solver who is empathetic to developer concerns and will employ construc

WPP is the trusted growth partner for the world’s leading brands. We unite cutting-edge media intelligence and data solutions, world-class creativity, next-generation production, transformative enterprise solutions and expert strategic counsel in a single company – powered by exceptional talent and our agentic marketing platform, WPP Open, to help our clients navigate change, capture opportunity and deliver transformational growth. We work with the world's most valuable brands and have global reach across 100+ markets, with deep local expertise. Our people are the key to our success. We're committed to fostering a culture of creativity, belonging and continuous learning, attracting and developing the brightest talent, and providing exciting career opportunities that help our people grow. For more information, visit WPP.com. Why we're hiring: We're looking for an Application & Development Security Lead to help shape and strengthen secure software development governance across one of the world's largest technology and creative ecosystems. Working within WPP's Digital Security & Risk Management team, you'll partner with engineering, product and platform teams to govern secure-by-design ways of working, improve software security governance, and provide oversight across modern development environments. This role isn't about writing code day-to-day. Instead, you'll influence governance of how secure software is built, deployed and maintained across cloud-native platforms, APIs, AI-enabled applications and global engineering teams. This is an opportunity to influence software security governance at global scale, helping shape how security supports innovation across one of the world's largest and most diverse technology environments. You'll work alongside talented security and engineering professionals while helping build secure, resilient products and platforms for the future. What you'll be doing: Define an

Altana is the network for trusted trade. Our AI-powered product network empowers governments and businesses to build a more resilient and secure global economy while keeping trade flowing. The Role: Vertical Technology Lead, Policy & National Security Altana’s mission is to power a new era of globalization organized around trusted networks. Nowhere is that mission more consequential — or more demanding — than in the policy and national security community, where the questions our customers bring us are matters of sovereignty, security, and how a nation understands the networks it depends on. These are the hardest programs we run. The technical bar is high and it keeps rising: the biggest opportunities are won, kept, and expanded on the strength of the technical work itself — sometimes on technical capability alone. As these engagements grow, so does the machinery large government partners expect from a serious partner: program management, delivery cadence, contractual rigor, accreditation. Left unmanaged, that machinery swamps the very people whose job is to architect and build. We’re changing how we deliver so it doesn’t. Large and strategic accounts are staffed with dedicated Implementation Delivery Managers (IDMs) who carry the program, project, and delivery-management load — and, as an account grows more complex, we trade up the team to meet it. That frees the technical leadership of the vertical to do what only it can do: hold the architecture bar, win the technical argument, and drive the last mile of product where the mission needs something that doesn’t exist yet. As Vertical Technology Lead for Policy & National Security, you own the technical outcomes for the vertical end-to-end. You are the senior technical counterpart to the vertical’s commercial leadership — setting the technical approach that wins business, owning the solution architecture and delivery that turns wins into mission outcomes, and leading the team that does the work. This is a UK-b

At Vanta, our mission is to help businesses earn and prove trust. We believe that security should be monitored and verified continuously, and we empower companies to practice better security and prove it with ease. Vanta has a kind and talented team, and while some have prior security experience, many have been successful at Vanta without it. Our Staff Software Engineers identify key strategic technical initiatives, deliver significant value to our customers and business, and set the tone for engineering excellence and culture. As an early engineering hire on the growing Privacy & Data Security team based in London, you will play a key role in bolstering our engineering presence in Europe. You'll partner with product management, product design, and your growing engineering team to drive the discovery and development of privacy features that expand Vanta’s value for its customers. Your work will accelerate product development and create a consistent customer experience for all of our customer segments. Vanta’s team and technology surface are growing quickly, and it’s essential that we invest in the right abstractions and systems to enable us to scale with our business. As a Staff Software Engineer, you’ll be responsible for identifying key strategic technical initiatives that impact our entire engineering team and deliver significant value to our business. You will set a high bar for engineering culture and excellence, and your past experience will be leveraged to enable and accelerate Vanta’s growth. Our business has found incredible product-market fit and has monetized effectively since the day we signed our first customer. We’re growing at a blistering pace, which presents career-defining opportunities for engineers to accelerate their growth and to contribute to a rapidly-scaling company. Vanta has a kind and talented team, and while some have prior security experience, many have been successful at Vanta without it. We’d love for you to join us! What you’ll d

Who are we? Cohere is the leading security-first enterprise AI company. We build cutting-edge foundation AI models and end-to-end products that are designed to solve real-world business problems. We’re training and deploying frontier models for enterprises who are building AI systems. We believe that our work is instrumental to the widespread adoption of AI and we are looking for folks that want to be part of that. We obsess over what we build. Each one of us is responsible for contributing to increasing the capabilities of our models and the value they drive for our customers. Cohere is a team of researchers, engineers, designers, and more, who are all passionate about their craft. We are a global technology company headquartered in Toronto with key offices in London, New York City, San Francisco, Montreal, Paris, Berlin and Seoul. Join us! Why this role? As a Member of Technical Staff in the Safety for Agents team, you will make a meaningful impact on the development of better, fairer, more trustworthy, and more secure Large Language Models (LLMs). Your primary focus will be on data generation, post-training algorithms, and evaluation methods to ensure Safety in the next generation of models that can access external resources and take actions in the world. You will work closely with other cross-functional machine learning teams and data annotation teams, and will also collaborate with product and policy teams. This role combines expertise in machine learning, ethical and responsible AI, experimental design, and data generation and management. It will require curiosity to tackle totally new scientific problems, engineering skills to implement the pieces we need to test solutions to these, and a desire to dive into messy data and results. You will be on a small team with a lot of autonomy and decision-making power, responsible for making the next generation of LLMs better for society as a whole. Please Note: The existing team work in offices in London, Edinburgh, Pa

About the Team OpenAI’s Network Security team designs and operates the secure, reliable connectivity behind our offices, labs, campuses, cloud environments, people, and devices. We combine strong network fundamentals with automation, observability, and close partnership across IT, Security, Research, Applied, and business teams. About the Role As a Network Engineer, you will design, operate, troubleshoot, and automate secure, reliable networks across offices, labs, cloud connectivity, and production services. You will balance strategic platform work—architecture, standards, roadmaps, lifecycle planning, and automation—with responsive operations such as incidents, escalations, break/fix, and time-sensitive delivery. We’re looking for broad network engineers who meet users where they are, lead with curiosity, own outcomes end-to-end, move with urgency grounded in security, and iterate with purpose. You will turn operational signals and recurring reactive work into durable systems and standards. In this role, you will: End-to-end ownership of secure enterprise routing, switching, wireless, WAN, network services, and cloud connectivity. A deliberate balance of strategic platform improvement and responsive troubleshooting, change safety, incident response, and operational delivery. Purposeful iteration through software, APIs, Infrastructure-as-Code, Git workflows, testing, and CI/CD that reduces recurring reactive work. You might thrive in this role if you have: End-to-end ownership of secure enterprise routing, switching, wireless, WAN, network services, and cloud connectivity. A deliberate balance of strategic platform improvement and responsive troubleshooting, change safety, incident response, and operational delivery. Purposeful iteration through software, APIs, Infrastructure-as-Code, Git workflows, testing, and CI/CD that reduces recurring reactive work. Compensation, Benefits and Perks This is a position with OpenAI UK Ltd., which controls the hiring and manageme

About the Team The Privacy Engineering team builds secure, reliable systems that help OpenAI meet its legal obligations while protecting user data. We partner closely with Legal and engineering teams across OpenAI to support lawful data access requests and other critical legal workflows. Our work turns complex, high-stakes processes into auditable and dependable technical systems with clear human oversight and strong privacy and security controls. About the Role We’re looking for a full-stack Software Engineer to build the internal tools and data pipelines that power lawful data access request workflows and Legal Operations. You will work across product and data systems to make authorized retrieval and case handling accurate, efficient, and auditable. This role is well suited to someone who enjoys translating ambiguous operational requirements into durable systems, cares deeply about sensitive-data handling, and wants to improve both technical reliability and the day-to-day experience of the people operating these workflows. In this role, you will: Design, build, and operate backend systems and workflow tooling for the full lifecycle of lawful data access requests, from intake and scoping through authorized retrieval, review, preparation, and audit. Build reliable data pipelines and interfaces across products and data stores so authorized teams can locate and handle the right records accurately and reproducibly. Implement least-privilege access, approval gates, provenance, audit trails, data minimization, and safe failure modes for sensitive workflows. Partner with Legal and Legal Operations to translate legal and operational requirements into clear technical designs and intuitive operator experiences. Identify responsible automation opportunities that reduce repetitive work while preserving human review, judgment, and accountability. Own production systems through testing, observability, incident response, documentation, and continuous reliability improvements. Hel