The Hidden Security Gap in Multi-Tenant MCP Servers
When you build a multi-tenant SaaS application or an MCP (Model Context Protocol) server that serves multiple organizations, cross-tenant data leakage is one of the most dangerous vulnerabilities you can ship. A single missing organizationId filter in a database query can expose one tenant's data to another — and traditional security scanners like Snyk, Semgrep, and CodeQL don't catch these patterns.
That's why I built mcp-tenant-isolation — a static analysis scanner with 57 deterministic rules specifically designed to catch tenant isolation failures in multi-tenant codebases.
What Is Tenant Isolation?
Tenant isolation ensures that data belonging to one organization (tenant) is never accessible to another. In a multi-tenant SaaS app, every database query, cache read, and file access must be scoped to the current tenant's organizationId.
