A machine token is a credential issued to a system or workload for authenticated access to an application, API, or service. Tokens are often short-lived, but if they are exposed, reused, or granted excessive scope, they can be abused in the same way as other non-human credentials.
Expanded Definition
A machine token is a non-human credential used by a workload, service, or automation path to authenticate to an API, application, or backend service. It is broader than a session token in day-to-day use because it is usually tied to repeatable machine-to-machine access, not a single interactive login.
Definitions vary across vendors on whether a machine token implies an opaque bearer token, a signed JWT, or a refreshable access token with a separate lifecycle. In NHI security, the important distinction is operational: the token represents a workload identity and should inherit the same controls expected for NIST SP 800-53 Rev 5 Security and Privacy Controls, including least privilege, rotation, and revocation. It is not the same thing as a user password, even though bearer-style tokens can function like one if stolen.
Machine tokens are often issued through CI/CD pipelines, cloud platforms, service brokers, or secret managers, then consumed automatically by code. Their security value depends on how tightly scope, TTL, audience, and storage are constrained. The most common misapplication is treating a machine token as a reusable static secret, which occurs when teams embed it in code, share it across workloads, or leave it valid after the associated service is decommissioned.
Examples and Use Cases
Implementing machine tokens rigorously often introduces lifecycle and automation overhead, requiring organisations to weigh fast service-to-service access against tighter issuance, rotation, and revocation controls.
- A CI/CD runner uses a short-lived machine token to pull artifacts from a registry, reducing standing credential exposure while still enabling unattended deployment.
- An internal API gateway issues a scoped token to one backend service so it can call a downstream billing service, with audience restrictions limiting token reuse elsewhere.
- A cloud automation job uses a machine token to query metadata and configuration data during incident response, then the token expires automatically after the task completes.
- A security team reviews exposed tokens after a breach and maps the incident to the patterns described in the Salesloft OAuth token breach, where stolen machine-accessible credentials enabled lateral abuse.
- Token sprawl in repositories and collaboration tools is evaluated against the patterns in the Guide to the Secret Sprawl Challenge, especially when tokens are copied into tickets, logs, or build output.
In practice, machine tokens are also used for federated access between agents and tools, but the security posture changes if the token can be replayed outside its intended audience. Industry usage is still evolving here, especially around agentic workflows and ephemeral delegation.
Why It Matters in NHI Security
Machine tokens matter because they often outlive the control assumptions that surrounded their creation. A token issued for automation may be exposed in a repo, copied into a chat thread, or inherited by a second application that was never part of the original trust boundary. NHIMG’s 2025 State of NHIs and Secrets in Cybersecurity reports that 44% of NHI tokens are exposed in the wild and that 91% of former employee tokens remain active after offboarding, showing how easily token governance breaks down when lifecycle controls are weak.
For NHI defenders, the core issue is not just exposure but replay potential: if a token is bearer-based and over-scoped, one leak can become a production compromise. That is why machine tokens should be tracked as first-class NHI assets with ownership, purpose, expiry, and revocation paths. The same discipline applies when tokens show up in pipelines, logs, or collaboration systems, a pattern reflected in the State of Secrets Sprawl 2026. Organisations typically encounter machine-token risk only after token reuse or unauthorized access is detected, at which point machine token governance 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 CSF 2.0, NIST SP 800-63, NIST Zero Trust (SP 800-207) and NIST AI RMF set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-02 | Machine tokens are NHI credentials that often fail through secret exposure and overuse. |
| NIST CSF 2.0 | PR.AC-1 | Access control principles apply when tokens authenticate systems instead of people. |
| NIST SP 800-63 | AAL2 | Token assurance should reflect the strength expected for non-interactive authenticated access. |
| NIST Zero Trust (SP 800-207) | SC-7 | Zero trust requires continuous validation of machine access and narrow trust scopes. |
| NIST AI RMF | Operational risk management covers automation credentials used by AI and service workflows. |
Use strong issuance, rotation, and revocation controls for machine token lifecycle management.
Related resources from NHI Mgmt Group
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Reviewed and updated by the NHIMG editorial team on August 26, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
