Senior Security Engineer - Pentester

About the job

Menlo Security is the leader in Browser Security for human and agentic workforces. Our mission is to enable humans and agents to connect, communicate, and collaborate securely, without compromise. The Menlo Browser Security Platform protects organizations from cyberattacks by stopping threats across the web, documents, and email before they reach the user. With Menlo Agent Runtime Security (MARS), that protection now extends to the AI agents working alongside every employee. Menlo Security is trusted by major global businesses, including Fortune 500 companies and government agencies, to protect their most valuable asset, their data, and is backed by top-tier investors.

Summary

We're looking for a forward-thinking Security Engineer to join our security team, focused on offensive and defensive testing, penetration testing of product features, and the cloud architecture behind the product. You'll operate across a complex multi-cloud environment (AWS & GCP) spanning traditional VMs and modern managed and unmanaged container-based architectures, partnering with fellow Penetration Testing and Cloud Security engineers to run targeted assessments during the testing window immediately before each release. The role reaches beyond the application layer into the Control Plane, reviewing cloud configurations, IAM policies, and orchestration layers against security baselines, and extends to the frontline of external defense by triaging bug bounty submissions and outside vulnerability reports. AI and large language models are core to how this team works day to day — you'll use them to accelerate reconnaissance, generate attack vectors, analyze configurations, and draft vulnerability reports, while applying human judgment to validate findings and communicate risk clearly to product teams. Speed matters here: the team's operating cadence is built around identifying, validating, and reporting vulnerabilities quickly enough to keep pace with release velocity.