Synthetic user store

A synthetic user store is a mock identity source used during development or testing instead of the real account database or directory. It can help a prototype move quickly, but it becomes a governance problem when code or tests rely on it as if it were production truth.

Expanded Definition

A synthetic user store is a stand-in identity source that mimics accounts, attributes, and lookup behaviour for development, testing, and staging. In NHI and IAM practice, it is useful when engineers need realistic identity flows without exposing production directories, service accounts, or secrets. The distinction matters: a synthetic store is meant to simulate identity, not govern it.

Definitions vary across vendors and teams, especially when the same pattern is used for unit tests, local development, integration tests, and demo environments. The operational risk begins when application logic, authorisation checks, or onboarding workflows depend on the synthetic store as if it were authoritative. That creates false confidence about account lifecycle, entitlement mapping, and failure handling. For a standards-based view of identity control, practitioners often anchor these design choices to NIST Cybersecurity Framework 2.0 and then apply identity-specific governance separately.

The most common misapplication is treating a synthetic user store as a long-lived source of truth, which occurs when test doubles are reused in production-like paths without explicit control boundaries.

Examples and Use Cases

Implementing a synthetic user store rigorously often introduces data-fidelity tradeoffs, requiring organisations to weigh faster testing against the risk of masking real identity and privilege behaviour.

• A development team seeds fake users to test login flows, but blocks any route that could create or modify real credentials.
• A CI pipeline uses synthetic identities to validate RBAC decisions without querying the production directory.
• An application team simulates expired tokens, disabled accounts, and missing claims to verify error handling before release.
• A security team uses a controlled test store to reproduce provisioning and deprovisioning defects found in service account workflows.
• Identity engineers compare synthetic records against production-like schema rules to catch integration drift before rollout, then document the gap in governance reviews using the Ultimate Guide to NHIs.

For implementation depth, teams often pair this with guidance from NIST Cybersecurity Framework 2.0 so the test identity model does not blur into production access controls.

Why It Matters in NHI Security

Synthetic user stores matter because they can hide the very failures NHI programmes are trying to prevent: stale privileges, broken revocation paths, and missing visibility into who or what can authenticate. If synthetic identities are allowed to drift from production realities, teams may ship code that assumes cleaner account states than actually exist. That weakens assurance for service accounts, API-driven workflows, and agentic systems that depend on accurate identity context. NHI Mgmt Group notes that only 5.7% of organisations have full visibility into their service accounts, which means many teams are already operating with incomplete identity truth; a misleading synthetic store can compound that blind spot. The related risks are discussed in the Ultimate Guide to NHIs.

Governance should therefore require explicit separation between mock identity sources and authoritative identity systems, plus review of any code path that consumes them. This is especially important where synthetic records are used to emulate high-privilege automation, because privilege assumptions can become embedded in tests and go unnoticed until an incident exposes the mismatch. Organisations typically encounter the cost only after a failed access review, a broken incident response run, or a missed deprovisioning event, at which point the synthetic user store becomes operationally unavoidable to address.

Related resources from NHI Mgmt Group

• What is the main risk when automation systems store ServiceNow credentials?
• When do service accounts become a higher risk than ordinary user accounts?
• How should security teams govern infrastructure identities alongside user identities?
• What is the difference between managing user accounts and managing NHIs?