Sr. Security Engineer, AppSec

Our Mission:

6sense is on a mission to revolutionize how B2B organizations create revenue by predicting customers most likely to buy and recommending the best course of action to engage anonymous buying teams. 6sense Revenue AI is the only sales and marketing platform to unlock the ability to create, manage and convert high-quality pipeline to revenue.

Our People:

People are the heart and soul of 6sense. We serve with passion and purpose. We live by our Being 6sense values of Accountability, Growth Mindset, Integrity, Fun and One Team. Every 6sensor plays a part in defining the future of our industry-leading technology. 6sense is a place where difference-makers roll up their sleeves, take risks, act with integrity, and measure success by the value we create for our customers.

We want 6sense to be the best chapter of your career.

Senior Security Engineer – Application Security (AI Security Focus)

Location: Romania, Remote

Reporting To: Manager, Security Engineering Function/Dept: Business Technology / Security

About the Role

You will drive platform security initiatives with a primary focus on securing AI/ML systems and models. You'll partner with engineering, product, and data science teams to ensure robust security for AI-powered features and infrastructure, while maintaining coverage for traditional AppSec domains.

Responsibilities & Accountabilities

• AI Security Leadership: Lead the design and implementation of security controls for AI/ML models, pipelines, and data flows.
• Vulnerability Management: Ensure coverage of AI/ML and application vulnerabilities using SAST, DAST, dependency scanning, and specialized AI security tools.
• Threat Modeling & Red Teaming: Conduct comprehensive threat modeling and AI/ML red teaming exercises, including prompt injection, jailbreaking, adversarial attack simulations, and vulnerability assessments for AI systems. Assess risks such as adversarial attacks, model theft, data poisoning, privacy risks, and other emerging threats to AI/ML models and pipelines.
• Automation & Tooling: Build and maintain automation pipelines for AI/ML security testing and monitoring.
• Cross-Functional Collaboration: Partner with Engineering, Product, and Data Science to embed security into AI/ML development lifecycles.
• Incident Response: Support detection, triage, and remediation of AI/ML-specific security incidents.
• Training & Advocacy: Facilitate secure development training focused on AI/ML risks and best practices.
• Metrics & Reporting: Track and report status of vulnerabilities, including AI/ML-specific metrics (e.g., model robustness, data integrity).
• Program Ownership: Design and execute quarterly OKRs for AI/ML security initiatives.

Performance Measurement

• Demonstrates deep understanding of AI/ML security risks and mitigations.
• Leads identification, triage, and management of AI/ML and application security issues.
• Establishes routines for updating documentation, runbooks, and dashboards with AI/ML security content.
• Effectively communicates complex AI/ML security topics to technical and non-technical stakeholders.

Educational and Experience Requirements

• 5+ years in information security, with significant experience in application security and AI/ML security.
• Hands-on experience securing AI/ML models, pipelines, and data within the AI/ML SDLC. · Familiarity with common AI/ML security threats (adversarial attacks, model inversion, data poisoning).
• Experience with security tools for AI/ML (e.g., Adversarial Robustness Toolbox, MLFlow security plugins).
• Development or scripting experience (Python preferred; experience with AI/ML frameworks a plus).
• Excellent communication skills.

Preferred Qualifications

• Bachelor's degree in a related field.
• Relevant certifications (e.g., AIRTP+, CAISF, Microsoft AI Security Fundamentals, AWS Certified Security – Specialty, GIAC, CISSP, CEH are highly desirable).
• Experience working directly with software developers and data scientists to improve code/model security.

Competencies and Behaviors

• Establishes credibility among Engineering and Data Science counterparts.
• Advocates for AI/ML security best practices.
• Drives tasks to completion and maintains accuracy of information.
• Effective prioritization and escalation to management.

Our Benefits:

Full-time employees can take advantage of health coverage, paid parental leave, generous paid time-off and holidays, quarterly self-care days off, and stock options. We'll make sure you have the equipment and support you need to work and connect with your teams, at home or in one of our offices.

We have a growth mindset culture that is represented in all that we do, from onboarding through to numerous learning and development initiatives including access to our LinkedIn Learning platform. Employee well-being is also top of mind for us. We host quarterly wellness education sessions to encourage self care and personal growth. From wellness days to ERG-hosted events, we celebrate and energize all 6sense employees and their backgrounds.

Equal Opportunity Employer:

6sense is an Equal Employment Opportunity and Affirmative Action Employers. Qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender perception or identity, national origin, age, marital status, protected veteran status, or disability status. If you require reasonable accommodation in completing this application, interviewing, completing any pre-employment testing, or otherwise participating in the employee selection process, please direct your inquiries to

We are aware of recruiting impersonation attempts that are not affiliated with 6sense in any way. All email communications from 6sense will originate from the domain. We will not initially contact you via text message and will never request payments. If you are uncertain whether you have been contacted by an official 6sense employee, reach out to jobs@