Principal Security Researcher

Northern Ireland, United Kingdom

7/25/2025

Security represents the most critical priorities for our customers in a world awash in digital threats, regulatory scrutiny, and estate complexity. Microsoft Security aspires to make the world a safer place for all. We want to reshape security and empower every user, customer, and developer with a security cloud that protects them with end to end, simplified solutions. The Microsoft Security organization accelerates Microsoft’s mission and bold ambitions to ensure that our company and industry is securing digital technology platforms, devices, and clouds in our customers’ heterogeneous environments, as well as ensuring the security of our own internal estate. Our culture is centered on embracing a growth mindset, a theme of inspiring excellence, and encouraging teams and leaders to bring their best each day. In doing so, we create life-changing innovations that impact billions of lives around the world.

Do you have a passion for helping Microsoft’s clients defend themselves against targeted exploitation?

Are you interested in being intimately involved in the latest, cutting-edge developments in the security industry and having a direct impact on the security of all Microsoft customers?

Do you want to be on the front lines of helping our customers go toe-to-toe against advanced adversaries?

Are you interested in a fast-paced job full of new opportunities?

If so, you may be a fit for a Principal Security Researcher role for the Global Hunting, Oversight, and Strategic Triage (GHOST) team!

We are looking for an experienced Principal Security Researcher with a strong analytical background to join our team to perform threat hunts, assist with investigations, develop threat intelligence, and to cultivate investigation best practices into Microsoft tooling and products. Researchers will support a global team to identify and catalog new attacker TTPs, victims, and deliver customer notifications to protect worldwide enterprise customers and empower customers to protect themselves via constantly improving Microsoft products.

Microsoft’s mission is to empower every person and every organization on the planet to achieve more. As employees we come together with a growth mindset, innovate to empower others, and collaborate to realize our shared goals. Each day we build on our values of respect, integrity, and accountability to create a culture of inclusion where everyone can thrive at work and beyond.

In alignment with our Microsoft values, we are committed to cultivating an inclusive work environment for all employees to positively impact our culture every day.

Responsibilities

Responsibilities:

This role is part of a collaborative team, assisting our customers with:

• Performing deep analysis of attacker activity in on-premises and cloud environments
• Identifying potential threats, allowing for proactive defence before an actual incident
• Notifying customers regarding imminent attacker activity
• Providing recommendations to improve customers’ cybersecurity posture going forward and performing threat intelligence knowledge transfer to prepare customers to defend against today’s threat landscape
• Building proof-of-concept and prototype threat hunting tools, automations, and new capabilities
• Driving product and tooling improvements by conveying learnings from threat hunting and incident response at scale to engineering partner teams
• Identifying, prioritizing, and targeting complex security issues that cause negative impact to customers. Creating and driving adoption of relevant mitigations and providing proactive guidance
• Working with others to synthesize research findings into recommendations for mitigation of security issues. Sharing across teams. Driving change within team based on research findings.
  
  

Qualifications

Required/Minimum Qualifications:

Experience in software development lifecycle, large-scale computing, modelling, cybersecurity, threat hunting and/or anomaly detection

OR Master's Degree in Statistics, Mathematics, Computer Science or related field.

Microsoft Cloud Background Check: This position will be required to pass the Microsoft Cloud background check upon hire/transfer and every two years thereafter.

Additional Or Preferred Qualifications

• Proficient experience in software development lifecycle, large-scale computing, modeling, cybersecurity, threat hunting and/or anomaly detection
• OR Doctorate in Statistics, Mathematics, Computer Science or related field.
• Proven knowledge of security fundamentals across Microsoft platforms (Client, Server, Cloud)
• Strong understanding of malware and the modern threat landscape, especially identity-based attacks
• Familiarity and understanding of SQL or Kusto Query Language (KQL) queries (or experience with large database/SIEM query languages such as Splunk/Humio/Kibana, etc.)
• Familiarity and understanding of Jupyter Notebooks, or building equivalent threat hunting automations with scripting languages
• Consulting background
• Active Directory subject matter expertise
• Experience with sophisticated threat actor evidence including familiarity with typical Indicators of Compromise (IOCs), Indicators of Activity (IOAs) and Tools, Techniques and Procedures (TTPs)
• Use of forensic analysis tools such as X-Ways Forensics®, WinHex®, Encase®, FTK®, etc
• Microsoft Azure and/or Office365 platform knowledge and experience
• Experience with various forensic log artifacts found in SIEM logs, web server logs, AV logs, protection logs such as HIDS and NIDS logs
• Familiarity with Microsoft Defender 365 security stack (for Endpoints, Identity, Cloud, etc), especially with Advanced Hunting query writing
• Excellent understanding of Windows internals and where trace evidence can be found
• Knowledge of third-party cybersecurity solutions, especially EDR and SIEM solutions
• Linux and/or macOS forensic analysis and threat hunting skills
• Technical certifications based on domain (e.g., Azure, SharePoint)
• Project Management certifications (e.g., PMP, Scrum)
• Investigation/Cybersecurity/Digital Forensics/DFIR certifications (e.g. CISSP, SANS GIAC, etc)
• Ability to obtain and maintain a Security Clearance.
  

Microsoft is an equal opportunity employer. Consistent with applicable law, all qualified applicants will receive consideration for employment without regard to age, ancestry, citizenship, color, family or medical care leave, gender identity or expression, genetic information, immigration status, marital status, medical condition, national origin, physical or mental disability, political affiliation, protected veteran or military status, race, ethnicity, religion, sex (including pregnancy), sexual orientation, or any other characteristic protected by applicable local laws, regulations and ordinances. If you need assistance and/or a reasonable accommodation due to a disability during the application process, read more about requesting accommodations.