Senior Application & AI Security Engineer

Job Description:

We’re KSM, one of the top 50 largest independent advisory, tax, and audit firms in the United States. But more than our size, it’s our people and culture that set us apart. We believe great things happen when people are supported, challenged, and given the freedom to do their very best work. That’s why we’ve built a workplace where your career and personal life can thrive together - where you have the flexibility to manage your time, the resources to grow, and a team that genuinely cares about your success.

We’ve been employee-owned since 2001, giving every team member a stake in our collective success. This ownership mentality fosters a culture of collaboration, curiosity, and excellence - where new ideas are welcomed, different perspectives are valued, and you’re encouraged to explore what excites you most. Whether you’re expanding your skills, tackling new challenges, or making an impact beyond the office, we provide the resources and support to help you grow in the direction that’s right for you.

At KSM, your contributions matter - not just to the firm, but to your colleagues, clients, and the communities we serve across the U.S. If you’re looking for a place where you can do meaningful work, build lasting relationships, and grow in ways that align with what’s most important to you, we’d love to meet you.

Position Summary

The Senior Application & AI Security Engineer is a hands-on individual contributor responsible for improving the security of KSM’s internally developed applications, APIs, AI-enabled solutions, and supporting integrations. This role partners directly with software developers, architects, and engineering teams to identify vulnerabilities, strengthen application designs, and implement and validate practical fixes. The engineer integrates security into application and AI development workflows, with particular attention to authentication, authorization, sensitive client data, and risks associated with large language models (LLMs), AI agents, and connected tools. Application and API security remain the primary focus of this position.

Key Responsibilities

• Assess internally developed applications and APIs for vulnerabilities involving authentication, authorization, access control, and sensitive data exposure.
• Perform hands-on application security testing, source code reviews, and architecture assessments; prioritize findings by exploitability and business impact.
• Partner with developers to design and implement fixes, then independently validate that identified vulnerabilities are resolved.
• Evaluate legacy applications, integrations, and application-to-application communications for security weaknesses.
• Improve API protections, including service authentication, object-level authorization, secrets management, rate limiting, and abuse prevention.
• Integrate practical security requirements and testing into the software development lifecycle and CI/CD pipelines.
• Implement and maintain appropriate SAST, DAST, software composition analysis, and secrets-scanning capabilities.
• Establish secure coding guidance and reusable patterns for traditional and AI-assisted development; review significant changes before production release.
• Review application and AI architectures across AWS, Azure, and development environments, including client-data isolation and access to sensitive information.
• Work with Security and Development to strengthen application, API, and AI integration logging, monitoring, and detection of unauthorized activity.
• Assess AI-enabled applications, LLM integrations, and agent workflows for prompt injection, sensitive data disclosure, insecure tool execution, and excessive permissions.
• Review how AI systems access, process, and transmit client information; evaluate controls for AWS Bedrock and other approved AI services.
• Develop practical security testing for AI features, including adversarial tests of LLM integrations and agent tool calls.
• Support investigations involving application or AI integration compromise and drive corrective actions to prevent recurrence.
• Track application security findings through remediation and communicate material risks, priorities, and progress to leadership.

Qualifications & Experience

Required

• 6+ years of hands-on experience in software development, application security engineering, or closely related technical roles.
• Strong knowledge of web application and API security, including authentication, authorization, session management, and access control.
• Demonstrated experience identifying, remediating, and validating vulnerabilities in production applications.
• Ability to read, understand, and review application source code and collaborate directly with software developers.
• Practical experience with application security assessments, manual testing, and code reviews.
• Familiarity with OWASP Top 10, OWASP API Security Top 10, and OWASP Top 10 for LLM Applications.
• Understanding of LLM application architectures, AI agent permissions, prompt injection, and the security implications of AI tool integrations.
• Experience securing REST APIs, service-to-service authentication, and application credentials.
• Experience incorporating security testing into CI/CD pipelines and software development workflows.
• Ability to work independently, prioritize effectively, and explain technical risks and remediation to developers and business stakeholders.

Preferred

• Professional software development experience in languages and frameworks used by KSM’s development teams.
• Experience securing applications and APIs hosted in AWS or Azure.
• Experience with SAST, DAST, software composition analysis, and secrets-scanning tools.
• Experience with application penetration testing, threat modeling, or secure architecture reviews.
• Experience protecting sensitive financial, personal, or confidential client information in multi-tenant applications.
• Familiarity with OAuth 2.0, OpenID Connect, SAML, and modern identity integration patterns.
• Experience improving application/API logging, monitoring, and detection capabilities, including AI integrations.
• Hands-on experience securing production AI applications or integrations, including AWS Bedrock or comparable platforms.
• Experience with AI security testing, adversarial evaluation, or assessing prompt injection and agent tool access.
• Relevant credentials such as OSWE, CSSLP, or GWAPT, or equivalent demonstrated expertise.

We are an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to age, color, sex, sexual orientation, gender identity, disability, genetic information, national origin, race, religion, veteran status, or any other protected category.

KSM only accepts resumes directly submitted by a candidate and referrals submitted by current KSM employees. Unsolicited resumes or candidate profiles sent by staffing agencies and fee-based referral services will not be considered outside of a signed KSM vendor contract. KSM will not pay a fee to recruiters or agencies that do not have a signed KSM vendor contract.