Security Engineer: Threat Modeling, AI Security & Automation

Valiant Technologies LLC; Sunnyvale (CA); On-site; USD 160,000 - 260,000; Full time

Job summary

Valiant Technologies LLC is recruiting a security engineer specializing in ERD security, threat modeling, and AI agent security. You will assess architecture, data flows, and third-party sharing across applications and cloud environments, with hands-on testing and tooling to improve risk mitigation.

The role emphasizes practical mitigations, collaboration with engineering and privacy teams, and the ability to implement automated security workflows and adversarial testing.

Qualifications

• 5+ years of relevant professional experience, including 3+ years in security engineering or a related security role.
• Experience conducting security design reviews, threat modeling, and privacy risk assessments.
• Hands-on penetration testing experience and a strong understanding of application, API, cloud, and data security.
• Software development or scripting experience, with the ability to build tools and automate security workflows.
• Familiarity with AI agent architectures and risks involving prompt injection, tool execution, permissions, and data access.

Responsibilities

• Conduct ERD security and privacy reviews across applications, APIs, cloud infrastructure, and AI systems, identifying risks in authentication, data handling, retention, and third-party sharing.
• Perform threat modeling, identify abuse cases, recommend mitigations, and work with engineering teams to address risks before deployment.
• Assess and test AI agents, including third-party and internally developed agents, through adversarial testing for data exposure, permissions, and external integrations.
• Build security automation tools and AI-assisted workflows to streamline reviews, evidence collection, and testing coverage.
• Conduct targeted penetration testing to validate security assumptions and identify exploitable vulnerabilities in services, APIs, and AI agents.
• Drive remediation and share knowledge by communicating findings, validating fixes, and developing guidance to prevent recurring issues.

Job description

Valiant Technologies LLC is recruiting a security engineer specializing in ERD security, threat modeling, and AI agent security. You will assess architecture, data flows, and third-party sharing across applications and cloud environments, with hands-on testing and tooling to improve risk mitigation.

The role emphasizes practical mitigations, collaboration with engineering and privacy teams, and the ability to implement automated security workflows and adversarial testing.