Penetration Tester – Cloud Security (M365)

About the role

Join the M365 Substrate security engineering team to protect Microsoft’s cloud services at a global scale. You will research, test, and harden the infrastructure that powers the world’s largest organizations, using cutting‑edge AI tools and creative attack techniques.

Key responsibilities

• Discover, validate, and exploit security vulnerabilities in M365‑backed infrastructure.
• Develop proof‑of‑concept exploits and conduct hands‑on penetration testing.
• Build and maintain automated tooling to scale offensive security testing.
• Collaborate with product groups to translate findings into actionable code fixes.
• Research emerging threats and create proactive security engagements.

Required profile

• Strong background in offensive security and vulnerability research.
• Experience working on large‑scale cloud services or SaaS platforms.
• Ability to work independently and contribute to a fast‑moving engineering environment.
• Growth‑mindset with a passion for continuous learning and innovation.

Required skills

• Penetration testing and exploit development.
• Vulnerability discovery and validation.
• Automation scripting for security testing.
• Familiarity with AI‑enhanced security tools.
• Code review and proof‑of‑concept development.

What we offer

• Access to the latest AI systems and cloud technologies.
• Opportunity to influence security for millions of users worldwide.
• Collaborative culture focused on inclusion, respect, and accountability.