Principal Threat Researcher

About Zscaler

Zscaler is a pioneer and global leader in zero trust security. The world’s largest businesses, critical infrastructure organizations, and government agencies rely on Zscaler to secure users, branches, applications, data & devices, and to accelerate digital transformation initiatives. Distributed across more than 160 data centers globally, the Zscaler Zero Trust Exchange platform combined with advanced AI combats billions of cyber threats and policy violations every day and unlocks productivity gains for modern enterprises by reducing costs and complexity.

Here, impact in your role matters more than title and trust is built on results. We believe in transparency and value constructive, honest debate—we’re focused on getting to the best ideas, faster. We build high-performing teams that can make an impact quickly and with high quality. To do this, we are building a culture of execution centered on customer obsession, collaboration, ownership and accountability. 

We champion an “AI Forward, People First” philosophy to help us accelerate and innovate, empowering our people to embrace their potential. If you’re driven by purpose, thrive on solving complex challenges and want to make a positive difference on a global scale, we invite you to bring your talents to Zscaler to help shape the future of cybersecurity.

Role

We are looking for a Principal Threat Researcher to join our Threat Detection Group within ThreatLabz. This is Hybrid role, reporting to a leader in ThreatLabz Team . You will track the evolving threat landscape, analysing emerging threats and identifying TTPs to develop critical detection and protection signatures. As part of our world-class research arm, you will ensure millions of global users remain protected through advanced malware research and behavioural analysis.

What you’ll do (Role Expectations)

• Analyse browser-based threats, including HTML smuggling and phishing, to develop robust protections

• Research vulnerabilities across OWASP, Web API, and LLM Top 10 to author prevention signatures

• Conduct static and dynamic malware analysis to mitigate emerging threats and C2 frameworks

• Develop complex automation tools and prototypes to integrate research findings into Zscaler products

• Contribute to the global security community by publishing in-depth threat analysis blogs and research papers

Who You Are (Success Profile)

• You thrive in ambiguity. You're comfortable building the path as you walk it. You thrive in a dynamic environment, seeing ambiguity not as a hindrance, but as the raw material to build something meaningful.

• You act like an owner. Your passion for the mission fuels your bias for action. You operate with integrity because you genuinely care about the outcome. True ownership involves leveraging dynamic range: the ability to navigate seamlessly between high-level strategy and hands-on execution.

• You are a problem-solver. You love running towards the challenges because you are laser-focused on finding the solution, knowing that solving the hard problems delivers the biggest impact.

• You are a high-trust collaborator. You are ambitious for the team, not just yourself. You embrace our challenge culture by giving and receiving ongoing feedback—knowing that candor delivered with clarity and respect is the truest form of teamwork and the fastest way to earn trust.

• You are a learner. You have a true growth mindset and are obsessed with your own development, actively seeking feedback to become a better partner and a stronger teammate. You love what you do and you do it with purpose.

What We’re Looking for (Minimum Qualifications)

• 7+ years of dedicated experience in Cyber Security Research with expertise in web attack and DOM/JS analysis

• Proficiency in browser security and analysing/deconstructing payloads within browser environments

• Hands-on experience with malware debugging and reverse engineering using tools like IDA, x64dbg, or Ollydbg

• Strong understanding of TCP/IP, Application layer protocols, and vulnerabilities across OWASP and LLM Top 10

• Experience with automation scripting in Python, Ruby, Go, or Shell to synthesise threat intelligence

What Will Make You Stand Out (Preferred Qualifications)

• Professional security certifications such as OSCP or specialised degrees in Computer Science or Information Technology

• Proven ability to implement AI-powered automation and leverage GenAI models for threat research

• Advanced reverse engineering experience specifically related to file-less threats and complex exploit techniques

#LI-Hybrid #LI-PM5

At Zscaler, we are committed to building a team that reflects the communities we serve and the customers we work with. We foster an inclusive environment that values all backgrounds and perspectives, emphasizing collaboration and belonging. Join us in our mission to make doing business seamless and secure.

Our Benefits program is one of the most important ways we support our employees. Zscaler proudly offers comprehensive and inclusive benefits to meet the diverse needs of our employees and their families throughout their life stages, including:

• Various health plans
• Time off plans for vacation and sick time
• Parental leave options
• Retirement options
• Education reimbursement
• In-office perks, and more!

Learn more about Zscaler’s Future of Work strategy, hybrid working model, and benefits here.

By applying for this role, you adhere to applicable laws, regulations, and Zscaler policies, including those related to security and privacy standards and guidelines.

Zscaler is committed to providing equal employment opportunities to all individuals. We strive to create a workplace where employees are treated with respect and have the chance to succeed. All qualified applicants will be considered for employment without regard to race, color, religion, sex (including pregnancy or related medical conditions), age, national origin, sexual orientation, gender identity or expression, genetic information, disability status, protected veteran status, or any other characteristic protected by federal, state, or local laws. See more information by clicking on the Know Your Rights: Workplace Discrimination is Illegal link.

Pay Transparency

Zscaler complies with all applicable federal, state, and local pay transparency rules.

Zscaler is committed to providing reasonable support (called accommodations or adjustments) in our recruiting processes for candidates who are differently abled, have long term conditions, mental health conditions or sincerely held religious beliefs, or who are neurodivergent or require pregnancy-related support.