Security Researcher / Vulnerability Hunter (San Francisco)

As a member of the Semmle Security Research Team your primary responsibility will be to find security vulnerabilities and zero-days in the most commonly used open source software. 

We measure our success by the quantity and the quality of CVEs that we find - not just the amount we find but how critical they are in nature. You will responsibly report every vulnerability that you find and apply for a CVE and will also share your expertise with others through blog posts, QL queries, and well-documented exploit PoCs
We take the ethics of what we do seriously and operate according to a clear disclosure policy. Any bug bounties that we receive, we donate to charity.

We use Semmle’s QL query language to analyze the source code and perform variant analysis - a new industry standard for security research that finds all variants of a known bug. We are building a team of experts to push the boundaries of Open Source Security through vulnerability research and variant analysis: we are looking for talented security researchers to join us and help us in securing software, together.

We are actively hiring for experienced Researchers in any of the following locations: Oxford (UK), Madrid, San Francisco, Seattle, New York, Buenos Aires, Copenhagen or we can consider remote working for highly experienced candidates. 

  Essential Requirements
  • Ability to find security vulnerabilities in source code.
  • Significant experience of code analysis / source code auditing.
  • A focus on one or more of the following languages: C, C++, C#, Java, Python, JavaScript or Go.
  • Prior exposure / participation / experience in Software Security (commercially, academically or through personal work like bounty bug hunting, CTFs or publishing CVE’s).
  • Enthusiasm for sharing your knowledge, by writing blog posts about your work and by publishing other technical details such as custom QL queries or well-documented PoCs.
  • Ethical attitude towards the handling and disclosure of vulnerabilities.

  Desirable skills (advantageous but not essential)
  • Proven track record of finding security vulnerabilities (ideally, you have already been credited for finding several CVEs).
  • Software development experience on large code bases.
  • Advanced debugging techniques.
  • Exploit development, including mitigation bypass techniques.
  • Program analysis / static analysis / language analysis.
  • Declarative programming (QL is a declarative language, descended from Datalog).

About Semmle
We believe security is a shared responsibility. Our mission is to secure all software by bringing the security and development communities together.

Our technology scales any organization's security expertise using QL to quickly explore any codebase to discover new vulnerabilities and all their variants. We empower product security teams to deliver variant analysis results to development teams using LGTM to ship safe code and protect their customers. Together, Semmle's platform enables the security community to collaborate and share their expertise in the field of variant analysis and security research. Our technology is free to use on open source projects using platform. At the time of writing, analysis results for over 135,000 projects are publicly available on

Security and software engineering teams at Google, Microsoft, NASA, Nasdaq and Uber depend on Semmle to secure their code. Headquartered in San Francisco, Semmle is a privately held company funded by Accel, with additional offices in Oxford, Copenhagen, New York City, Seattle, and Valencia.

How do you apply?
Semmle aims to hire outstanding people who have a diversity of perspectives, ideas and cultures. We actively support diversity and inclusion in the workplace and are committed to equal employment opportunity regardless of race, colour, ancestry, religion, sex, national origin, sexual orientation, gender identity, age, citizenship, marital status or disability status.

Please complete the following form to apply or feel free to get in touch with Zac Wallis at for more information.  |

Want to apply later?

Type your email address below to receive a reminder

Apply to Job

ErrorRequired field
ErrorRequired field
ErrorRequired field