Senior AI Security Security

Summary 

The Senior AI Security Engineer is the senior technical owner for the day-to-day security of OneStream’s internal AI environment. As the company expands its use of AI, this role drives the technical execution of the internal AI security strategy, ensuring internal AI platforms, connectors, agents, and workflows are deployed securely, and is accountable for the outcomes. 

The Senior AI Security Engineer co-develops and executes the internal AI security roadmap with the AI Security Architect/Manager, architects and operates the company’s AI Detection and Response (AIDR) capability, sets the standard for security reviews of new and third-party AI tooling, and makes independent risk decisions on behalf of the Security team. The role also owns the metrics that measure internal AI security success, serves as the Security team’s AI automation champion, and acts as technical lead and mentor for additional AI Security team members as the function grows. 

This is a senior, hands-on, high-autonomy role that reports to the AI Security Architect/Manager and partners with IT, Legal, Compliance, and business leaders to enable the organization to adopt AI securely. 

Primary Duties and Responsibilities 

• Serve as the senior technical owner for the day-to-day security of OneStream’s internal AI environment, including enterprise AI assistant platforms, agents, connectors and tool integrations such as MCP, and AI-enabled business workflows, from intake through production; co-develop and execute the internal AI security roadmap with the AI Security Architect/Manager. 
• Define and own the security review standard for enterprise AI assistant and agent configurations, connectors, and workflows, including tenant-level controls, permissions, data-sharing and retention settings, integration configurations, and custom agents and skills; make independent approval decisions and set the secure-by-default baselines that internal AI builders follow. 
• Architect, implement, and own the AI Detection and Response (AIDR) capability end to end: monitor AI usage across the enterprise, detect prompt injection, tool abuse, data exfiltration, and anomalous agent behavior, and integrate alerting and response into Security Operations workflows. 
• Lead and set the standard for security reviews of new and third-party AI tooling, including AI-enabled SaaS features, connectors, MCP servers, and models, against OneStream security policies and procedures, and serve as the escalation point for complex or high-risk reviews. 
• Serve as the Security team’s AI automation champion: identify opportunities to incorporate AI into security operations, such as alert triage and enrichment, detection engineering, and vulnerability management, and lead the design and delivery of those workflows to multiply the team’s capacity. 
• Lead threat modeling of internal AI use cases against AI-specific attack classes, including prompt injection, jailbreaks, tool misuse, excessive agency, sensitive data leakage, and AI supply-chain risk, and influence architecture decisions across IT and Engineering. 
• Define, implement, and own the metrics program for internal AI security, and report AI security posture and program progress to Security leadership. 
• Operationalize AI governance by partnering with IT, Legal, Privacy, and business teams to translate AI acceptable use, data classification, and security policies into technical guardrails, secure-by-default patterns, review checklists, and training that enable employees and internal AI builders to adopt AI securely. 
• Act as incident lead for security incidents involving internal AI systems: investigate, contain, and remediate AI-related incidents and drive lessons learned into controls and detections. 
• Monitor the emerging AI threat landscape and frontier model capabilities and translate developments into updated controls, detections, and guidance for the organization. 
• Provide technical leadership and mentorship to AI Security team members, including onboarding and guiding future AI Security hires, and raise AI security capability across the broader Security team.  

Required Education and Experience 

• Bachelor’s degree in Computer Science, Cybersecurity, or a related field, or equivalent experience. 
• 6+ years of experience in security engineering, security operations, application security, or a related security discipline, including military or government cybersecurity roles. 
• At least 1–2 years of demonstrated hands-on experience securing or building with LLM-based systems, such as enterprise AI assistants, agents, tool-calling and connector integrations, or retrieval-augmented workflows. 
• Demonstrated track record of owning a security program, capability, or major initiative end to end, including setting technical direction and making independent risk decisions. 
• Working knowledge of AI-specific threats (prompt injection, jailbreaks, tool abuse, data exfiltration through agents) and frameworks such as the OWASP Top 10 for LLM Applications, MITRE ATLAS, and the NIST AI Risk Management Framework. 
• Experience reviewing SaaS security posture, identity and access controls, and least-privilege and data-sharing configurations. 
• Experience conducting third-party and vendor security risk assessments and driving remediation with vendors and internal owners. 
• Experience with detection engineering, SIEM and log analysis, and building monitoring and alerting for new data sources. 
• Proficiency in scripting and automation (Python or similar), working with APIs, and integrating tools and platforms. 
• Strong written and verbal communication skills, with the ability to explain AI risk and trade-offs to technical and non-technical stakeholders, including Security leadership and executives. 

Preferred Education and Experience 

• Demonstrated leadership and cross-functional collaboration, such as leading or mentoring engineers, partnering with IT, Legal, Compliance, and business teams to deliver shared outcomes, building consensus, and influencing decisions without direct authority. 
• Experience administering and securing enterprise AI assistant platforms, including connector, agent, and MCP server configurations. 
• Experience with integration or automation platforms (iPaaS) and API gateways as security control points for AI connectors. 
• Experience building AI-assisted security operations automation, such as LLM-driven alert triage, enrichment, or SOAR workflows. 
• Experience with adversarial testing or red-teaming of LLM applications and agents. 
• Experience building a new security capability or function from the ground up. 
• Security certifications such as CISSP, CCSP, OSCP, GIAC, or AI-security-specific credentials. 
• Experience in a SaaS or software company and familiarity with SOC 2, ISO 27001, or similar compliance frameworks. 

Knowledge, Skills, and Abilities 

• AI & LLM Security 
• Detection Engineering & Incident Response 
• Security Architecture & Least-Privilege Design 
• Third-Party & Vendor Risk Assessment 
• Security Automation & Scripting 
• Threat Modeling 
• Security Metrics & Program Measurement 
• Cross-Functional Influence & Communication 
• Technical Leadership & Mentorship 
• Ownership & Autonomy: takes day-to-day technical ownership of internal AI security, prioritizes effectively across a fast-growing set of AI tools and workflows, makes sound risk decisions with incomplete information, and enables the business to adopt AI quickly without sacrificing security. 

Benefits at OneStream  
OneStream employees are passionate, hardworking individuals who go above and beyond to keep our customers happy and follow through on our mission statement. They consistently deliver the best and in turn, we make every effort to keep them cared for and happy. A sample of the benefits we provide are:

• Excellent Medical Plan
• Dental & Vision Insurance
• Life Insurance
• Short & Long Term Disability
• Vacation Time
• Paid Holidays
• Professional Development
• Retirement Plan