Researcher Web Security, Detection

About Us
At Cloudflare, we are on a mission to help build a better Internet. Today the company runs one of the world's largest networks that powers millions of websites and other Internet properties for customers ranging from individual bloggers to SMBs to Fortune 500 companies. Cloudflare protects and accelerates any Internet application online without adding hardware, installing software, or changing a line of code. Internet properties powered by Cloudflare all have web traffic routed through its intelligent global network, which gets smarter with every request. As a result, they see significant improvement in performance and a decrease in spam and other attacks. Cloudflare was named to Entrepreneur Magazine's Top Company Cultures list and ranked among the World's Most Innovative Companies by Fast Company.
At Cloudflare, we're not looking for people who wait for a polished roadmap; we're looking for the builders who see the cracks in the Internet that everyone else has simply learned to live with. We value candidates who have the instinct to spot a "normalized" problem and the AI-native curiosity to create a solution using the latest tools. Our culture is built on iteration, leveraging AI to ship faster today to make it better tomorrow, while ensuring that every improvement, no matter how small, is shared across the team to lift everyone up. If you're the type of person who values curiosity over bureaucracy, and that AI is a partner in solving tough problems to keep the Internet moving forward, you'll fit right in.
Location- New York, NY
About the Department
Cloudflare's Engineering Team is home to some of the industry's top engineers, dedicated to building and scaling innovative software that handles a huge proportion of the Internet. Our Detection department sits at the heart of that mission: we identify automated, fraudulent, and malicious activity across the Internet and through our gateway. We develop advanced detection systems and machine learning models that operate at scale, collaborating with Product and Engineering teams across the company to protect our customers and stay ahead of the constantly evolving threat landscape.
What You'll Do

• Study our adversaries deeply - reverse-engineer bot tools, automation frameworks, and fraud kits to understand how they work and how they evolve.
• Play the cat-and-mouse game: probe our own detections like an attacker would, close the gaps, and stay a step ahead as adversaries adapt.
• Track the bot and fraud ecosystem through tooling, marketplaces, and emerging techniques. Turn that intelligence into actionable detection signals.
• Develop heuristics, signatures, and detection ideas grounded in real adversary behavior, partnering with Data Scientists and Engineers to bring them to life.
• Design mitigations that neutralize attackers without tipping our hand; preserving our detection signals rather than teaching adversaries how to evade them.
• Automate the work analysts do by hand by turning manual investigation and rule-writing into scalable, automated detection.

Must Haves
You know our adversaries. You understand bots, automation, and the tooling used to attack web applications at scale.

• Deep web expertise. You know HTTP, TLS, browser internals, fingerprinting, CAPTCHAs, and the techniques used to evade them.
• You love the hunt. You enjoy ethical hacking and reverse engineering, with an adversarial mindset that assumes every defense can be broken - and the creativity to prove it.

Who You Are

• From research to detection. You translate what you learn about attackers into concrete signals defenders can use.
• Mitigation without burning signals. You understand (or are curious to learn) how to act on attackers without burning the signals that make them detectable.
• Disciplined in code. You script comfortably (e.g., Python, JavaScript) to build proofs-of-concept and tooling - and you write it cleanly, whether it's throwaway or meant to last.
• Clear communicator. You explain complex attacker behavior to technical and non-technical audiences alike.

Compensation

• Compensation may be adjusted depending on work location.
• For New York based hires: Estimated annual salary of $150,000 - $185,000.

Equity

• This role is eligible to participate in Cloudflare's equity plan.

Benefits

• Cloudflare offers a complete package of benefits and programs to support you and your family. Our benefits programs can help you pay health care expenses, support caregiving, build capital for the future and make life a little easier and fun! The below is a description of our benefits for employees in the United States, and benefits may vary for employees based outside the U.S.
• Health & Welfare Benefits
• Medical/Rx Insurance
• Dental Insurance
• Vision Insurance
• Flexible Spending Accounts
• Commuter Spending Accounts
• Fertility & Family Forming Benefits
• On-demand mental health support and Employee Assistance Program
• Global Travel Medical Insurance
• Financial Benefits
• Short and Long Term Disability Insurance
• Life & Accident Insurance
• 401(k) Retirement Savings Plan
• Employee Stock Participation Plan
• Time Off
• Flexible paid time off covering vacation and sick leave
• Leave programs, including parental, pregnancy health, medical, and bereavement leave

What Makes Cloudflare Special?
We're not just a highly ambitious, large-scale technology company. We're a highly ambitious, large-scale technology company with a soul. Fundamental to our mission to help build a better Internet is protecting the free and open Internet.
Project Galileo: Since 2014, we've equipped more than 2,400 journalism and civil society organizations in 111 countries with powerful tools to defend themselves against attacks that would otherwise censor their work, technology already used by Cloudflare's enterprise customers--at no cost.
Athenian Project: In 2017, we created the Athenian Project to ensure that state and local governments have the highest level of protection and reliability for free, so that their constituents have access to election information and voter registration. Since the project, we've provided services to more than 425 local government election websites in 33 states.
1.1.1.1: We released 1.1.1.1 to help fix the foundation of the Internet by building a faster, more secure and privacy-centric public DNS resolver. This is available publicly for everyone to use - it is the first consumer-focused service Cloudflare has ever released. Here's the deal - we don't store client IP addresses never, ever. We will continue to abide by our privacy commitment and ensure that no user data is sold to advertisers or used to target consumers.
Sound like something you'd like to be a part of? We'd love to hear from you!
Please note that applicants who progress to the offer stage of the interview process may be asked to attend an in-person interview within one of the Cloudflare Offices or Cloudflare Hubs. More details about this will be available at that stage of the interview process.
This position may require access to information protected under U.S. export control laws, including the U.S. Export Administration Regulations. Please note that any offer of employment may be conditioned on your authorization to receive software or technology controlled under these U.S. export laws without sponsorship for an export license.
Cloudflare is proud to be an equal opportunity employer. We are committed to providing equal employment opportunity for all people and place great value in both diversity and inclusiveness. All qualified applicants will be considered for employment without regard to their, or any other person's, perceived or actual race, color, religion, sex, gender, gender identity, gender expression, sexual orientation, national origin, ancestry, citizenship, age, physical or mental disability, medical condition, family care status, or any other basis protected by law. We are an AA/Veterans/Disabled Employer.
Cloudflare provides reasonable accommodations to qualified individuals with disabilities. Please tell us if you require a reasonable accommodation to apply for a job. Examples of reasonable accommodations include, but are not limited to, changing the application process, providing documents in an alternate format, using a sign language interpreter, or using specialized equipment. If you require a reasonable accommodation to apply for a job, please contact us via e-mail at [email protected] or via mail at 101 Townsend St. San Francisco, CA 94107.