Security Researcher II

Microsoft Security is committed to making the world safer in an era of rapidly evolving digital threats and determined human adversaries. The Microsoft Defender Experts (DEX) team combines deep security expertise with Microsoft security products, telemetry, threat intelligence, and partnerships across the company to help customers detect, investigate, understand, and respond to advanced threats. Within DEX Operations, Threat Researchers operate where customer defense, threat hunting, incident investigation, and detection innovation meet. We are curious, collaborative, and comfortable working through uncertainty. We learn from real-world attacks, turn frontline insights into stronger protection, and continuously improve how we defend customers at global scale. We are looking for an experienced Threat Researcher to join the DEX Operations team. You will investigate suspicious activity across customer environments, hunt for sophisticated adversaries, perform root-cause analysis, and transform complex security data into clear, actionable protection outcomes. You will use broad telemetry across the Microsoft Defender ecosystem and other security platforms to identify attacker behavior, surface detection gaps, and help customers respond quickly and confidently. This role offers the opportunity to work on high-impact security challenges, explore emerging attacker tradecraft, and build hunting approaches, detections, and automation with experts across security operations, threat intelligence, research, engineering, and data science. The work is technically demanding and constantly evolving. Your discoveries can influence immediate customer protection as well as longer-term product and detection improvements.

1. Bachelor's or master's degree in computer science, cybersecurity, engineering, or a related technical field, or equivalent practical experience.
2. 4+ years of cybersecurity experience in one or more areas such as security operations, threat hunting, incident response, digital forensics, malware analysis, threat intelligence, penetration testing, or red teaming.
3. Hands-on experience investigating security incidents and hunting across large security datasets using SIEM, EDR/XDR, or comparable security platforms.
4. Coding or scripting experience with one or more of Python, KQL, SQL, regular expressions, PowerShell, or similar languages.
5. Working knowledge of threat analysis models and frameworks such as the Cyber Kill Chain and MITRE ATT&CK.
6. Understanding of common enterprise attack surfaces, including endpoints, identity, email, cloud services, networks, and authentication systems.
7. Ability to analyze complex technical evidence, form and test hypotheses, and translate findings into clear actions.
8. Strong written and verbal communication skills in English, with the ability to brief investigations and collaborate across teams.

Global mission: Help defend enterprise customers around the world against sophisticated and fast-moving threats. Cutting-edge work: Investigate emerging adversary behavior and solve security problems that do not yet have established playbooks. Latest technology: Work with rich Microsoft security telemetry, modern security analytics, threat intelligence, cloud-scale data, automation, and evolving AI-assisted capabilities. End-to-end impact: Connect live customer investigations to better hunting, stronger detections, improved operational workflows, and product feedback. Expert community: Collaborate with specialists across Microsoft Security and learn from diverse perspectives in research, operations, engineering, data science, and incident response. Continuous challenge: Expand your skills across platforms, attack surfaces, and adversary techniques while making decisions in ambiguous, high-impact situations.