Secure AI Access to Customer Financial Data
A reference architecture for identity, AI agents and MCP, APIs, and SOC 2 controls in SaaS platforms.
Customers increasingly expect to ask an AI assistant about their own accounts. This paper shows how to let an external user sign in to a SaaS application and reach their financial data through an AI assistant, without giving the agent more access than the customer has and while leaving evidence an auditor can test.
What's inside
- How AI changes the threat model: prompt injection, confused deputy, token passthrough
- Five design principles for user-bound, least-privilege AI access
- Reference architecture with 16 numbered control points
- Authentication and delegation flow, from OIDC + PKCE to RFC 8693 token exchange
- Technical and program controls mapped to SOC 2 criteria with audit evidence
- Crosswalk to NIST SP 800-53 Rev. 5 and the NIST AI RMF, plus a three-phase roadmap
For security architects, GRC and audit professionals, and technology leaders building AI features on regulated data. Reference design for educational purposes; not legal or audit advice.