A synthetic identity is a software-based actor that can authenticate, request access, and execute actions without being a human user. In practice, this includes AI agents, bots, service accounts, tokens, and other machine identities that need clear ownership, scope, and revocation.
Expanded Definition
Synthetic identity is a broad NHI security term for any software-based actor that can authenticate and act on systems without a human owner at the keyboard. In practice, the category includes AI agents, bots, service accounts, API keys, tokens, certificates, and MCP-connected tools that execute work with delegated authority. Definitions vary across vendors, but the operational test is simple: if the entity can obtain access, request data, or trigger actions, it must be governed as an identity.
That distinction matters because synthetic identities are not just “automation.” They carry scope, permissions, secrets, lifecycle state, and revocation requirements just like human users do, but often with less visibility. NHI governance guidance from Ultimate Guide to NHIs treats them as first-class identities, while identity assurance concepts in NIST Cybersecurity Framework 2.0 reinforce the need to know what is active, authorized, and monitored.
The most common misapplication is treating a synthetic identity as a disposable technical artifact, which occurs when teams issue long-lived credentials without ownership, expiration, or review.
Examples and Use Cases
Implementing synthetic identity governance rigorously often introduces operational friction, requiring organisations to weigh automation speed against the cost of tighter issuance, monitoring, and revocation controls.
- An AI agent uses an MCP tool to open tickets, query internal systems, and update records. If the agent can act across systems, it should have explicit ownership, scope limits, and revocation tied to its purpose.
- A CI/CD service account signs builds and deploys containers. If its secret is embedded in pipeline variables, that identity can become a persistent breach path, which is why the JetBrains GitHub plugin token exposure remains a useful cautionary example.
- A bot pulls customer data for analytics every hour. The identity should be limited with RBAC and short-lived credentials, because persistent entitlements make automation harder to contain after compromise.
- A third-party integration authenticates with an API key to sync records. The key is a synthetic identity and should be tracked through provisioning, rotation, and offboarding, not left as an undocumented integration secret.
For deeper context on identity sprawl and incident patterns, see 52 NHI Breaches Analysis and the broader NHI lifecycle guidance in Ultimate Guide to NHIs — What are Non-Human Identities. The operational pattern aligns with the identity governance emphasis in NIST Cybersecurity Framework 2.0.
Why It Matters in NHI Security
Synthetic identities are often the most privileged and least supervised actors in an environment, which makes them ideal for attackers once secrets, tokens, or service credentials are exposed. NHI Mgmt Group research shows that Ultimate Guide to NHIs found 97% of NHIs carry excessive privileges, and only 5.7% of organisations have full visibility into their service accounts. That combination turns a convenience mechanism into a high-value attack path.
Understanding the term also clarifies the security model for Zero Trust, because synthetic identities need the same discipline as human identities: least privilege, strong authentication, continuous verification, and prompt revocation. The guidance in Top 10 NHI Issues and breach analysis in Cisco DevHub NHI breach show how quickly unmanaged machine access becomes a systemic problem. The same logic supports the trust boundaries described in NIST Cybersecurity Framework 2.0.
Organisations typically encounter synthetic identity risk only after a token leak, abnormal API activity, or unauthorized automation event, at which point the identity becomes operationally unavoidable to address.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
OWASP Non-Human Identity Top 10 address the attack and risk surface, while NIST Zero Trust (SP 800-207) and NIST CSF 2.0 set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-02 | Covers secrets, tokens, and machine identities that lack clear ownership or rotation. |
| NIST Zero Trust (SP 800-207) | Zero Trust requires continuous verification for all identities, human and machine. | |
| NIST CSF 2.0 | PR.AC-4 | Access permissions management maps directly to machine identity entitlement control. |
Review synthetic identity entitlements regularly and remove standing access that is no longer needed.
