TL;DR: ISO 27001 links access control, cryptographic controls, operational security, supplier relationships, and incident management to non-human identities such as service accounts, API keys, tokens, certificates, and automation tools, according to Entro Security. The governance gap is that machine identities are often over-privileged, long-lived, and under-monitored, so compliance depends on treating them as first-class identities rather than edge cases.
At a glance
What this is: This is an analysis of how ISO 27001 control expectations map onto non-human identities, with the central finding that machine access becomes a compliance gap when it is over-privileged, long-lived, or poorly monitored.
Why it matters: It matters because IAM, PAM, and NHI programmes cannot close an ISO 27001 gap if service accounts, API keys, and automation credentials remain outside the same governance discipline applied to people.
Context
ISO 27001 compliance for machine identities starts with a simple governance problem: most programmes still treat non-human identities as operational plumbing rather than governed identities. That assumption breaks once service accounts, API keys, tokens, certificates, and automation tools can access production systems and sensitive data.
Entro Security's framing is that the control gap is not whether ISO 27001 applies to machines. It is whether organisations have extended access control, cryptographic protection, logging, supplier oversight, and incident response to the identities that software and services use without human intervention.
For IAM, PAM, and NHI teams, the practical issue is not documentation alone. It is whether the organisation can inventory these identities, bound their privilege, rotate their secrets, and prove that they are monitored and revoked with the same rigor as human access.
Key questions
Q: What breaks when service account lifecycle controls are missing in an ISO 27001 environment?
A: The ISMS can still exist on paper, but the organisation loses the ability to prove that access is limited, reviewable, and removed when no longer needed. Missing lifecycle controls create stale credentials, unclear ownership, and weak evidence for auditors. In practice, that turns identity into an unmanaged exception path.
Q: Why do long-lived machine credentials create more risk than short-lived access?
A: Long-lived machine credentials create more risk because they can be copied, reused, and forgotten across pipelines and infrastructure. Short-lived access reduces exposure, but only if it is tied to policy, ownership, and revocation at the point of use. Without that, the credential may still outlive the system or workload it was meant to protect.
Q: What are the signs that a non-human identity program is failing?
A: A failing program usually looks organized on paper but inactive in practice. Common signs include a large inventory with no accountable owner, quarterly exports assembled by hand, dormant accounts that nobody will revoke, and remediation lists that stop moving after the first objection. If discovery exists but revocation authority does not, the program is producing reporting work, not control.
Q: How should teams handle third-party machine access under ISO 27001?
A: Treat supplier-issued tokens, service accounts, and API keys as scoped access that must expire, be monitored, and be revoked when the commercial or technical relationship changes. Supplier governance only works when offboarding includes credential removal, not just contract closure or ticket closure.
Technical breakdown
Why non-human identities sit inside the ISO 27001 control model
Non-human identities are credentials used by systems, applications, and services to authenticate and authorise access without a person in the loop. In ISO 27001 terms, they fall under the same control logic as any other identity because they can read data, move between systems, and invoke privileged functions. The article maps this to access control, cryptographic controls, operational security, supplier relationships, and incident management. The technical problem is that machine identities are often provisioned once and then forgotten, which creates standing access that is difficult to monitor or justify over time.
Practical implication: treat service accounts and API keys as governed identities, not configuration artefacts.
How over-privileged machine access creates audit and breach exposure
The article highlights least privilege, RBAC, separation of duties, logging, and regular audits as the core control set. Technically, the risk comes from identities that can perform more actions than the workload needs, or that are reused across multiple systems and environments. That widens blast radius if a key or token is exposed, and it also weakens evidence quality during an audit because the access path is hard to explain. ISO 27001 compliance therefore depends on proving that each non-human identity has a bounded purpose, bounded scope, and bounded lifetime.
Practical implication: reduce standing privilege and make each non-human identity individually reviewable.
Why secrets handling and supplier access are the same control problem
ISO 27001's cryptographic and supplier controls converge when third-party services rely on machine credentials. API keys, service account passwords, and certificates must be stored securely, transmitted safely, and revoked when a relationship changes. From an identity perspective, the important point is that an external supplier's access is still access, even if it is delivered through a token or integration rather than a named user. If those credentials are not tied to lifecycle, expiration, and monitoring, the organisation loses control of the trust boundary.
Practical implication: align vaulting, expiration, and offboarding for third-party machine credentials with supplier governance.
Threat narrative
Attacker objective: The attacker aims to abuse trusted machine access to reach sensitive data or internal systems without triggering the same controls normally applied to human users.
- Entry occurs when a service account, API key, or certificate is exposed, reused, or left in place after its intended purpose has ended.
- Escalation follows when that identity carries broader permissions than the workload needs, allowing access to additional systems or data sets.
- Impact is realised when the compromised machine identity is used to exfiltrate information, disrupt operations, or pivot into other trusted services.
Breaches seen in the wild
- Dropbox Sign breach 2024: A compromised back-end service account gave attackers Dropbox Sign customer data, including API keys, OAuth tokens and MFA information.
- Cloudflare Thanksgiving breach 2023: One service token and three service accounts left unrotated after the Okta breach gave a nation-state attacker access to Cloudflare's Atlassian systems.
Read our 52 NHI Breaches Analysis report for a comprehensive view of breaches impacting Non-Human Identities including AI Agents.
NHI Mgmt Group analysis
ISO 27001's identity model is incomplete until machine identities are governed as identities. The standard is often interpreted through human access patterns, but the article shows that service accounts, API keys, tokens, and certificates sit inside the same control plane. If an organisation can audit people but not automation, it does not yet have a complete ISMS view. Practitioners should treat NHI inventory and lifecycle control as part of ISO 27001 evidence, not as an adjacent operations task.
Over-privileged NHI is the control gap, not just a hardening issue. A machine identity with broad access, long lifespan, and weak monitoring changes the meaning of least privilege because its blast radius is structurally larger than the workload requires. That gap shows up in access control, operational logging, and incident response all at once. The practical conclusion is that NHI privilege design must be reviewed as a compliance object, not merely a security tuning exercise.
Secret leakage and secret longevity are the same governance failure when ISO 27001 is the target. Encryption and vaulting matter, but they do not solve the problem if credentials remain valid long after their intended use. The control expectation is that the organisation can prove who can use the secret, for what purpose, and until when. That is a lifecycle question, and lifecycle ownership must sit with identity governance rather than with platform teams alone.
Supplier relationships expose the weakest point in machine identity governance. Third-party access delivered through tokens or service accounts can bypass the social cues and approval paths that exist for human access, which makes offboarding and expiration the decisive controls. If a supplier relationship changes but the credential does not, accountability has already drifted. Practitioners should read ISO 27001 supplier controls as a mandate to govern external machine access with the same discipline used for privileged human accounts.
From our research library:
- NHIs outnumber human identities by 25x to 50x in modern enterprises, according to the Ultimate Guide to NHIs.
- Read next: Guide to NHI Rotation Challenges
What this signals
Identity governance for ISO 27001 now has to cover machines first, not last. The programme question is whether your inventory, ownership, and lifecycle controls can distinguish a legitimate workload credential from an orphaned one. If they cannot, access control evidence is not reliable enough for a defensible ISMS.
Machine identity governance becomes measurable when secret lifetime is tied to review cadence. A secret that never expires is a policy exception wearing the appearance of normal operations, and that should be treated as a control design flaw rather than an operational inconvenience. The decisive shift is from platform ownership to lifecycle ownership.
Service-account drift: identities created for integration work often outlive the service they support, which means the control problem is not only compromise but forgotten trust. Teams should expect their ISO 27001 evidence to fail if they cannot show active revocation paths and current ownership for these accounts.
For practitioners
- Inventory every non-human identity in scope Build a current register of service accounts, API keys, tokens, certificates, automation users, and third-party credentials, then assign an owner and a purpose to each one.
- Apply least privilege to machine access Review each identity's permissions against the task it actually performs and remove access paths that are not required for the workload or integration.
- Rotate and retire long-lived secrets Set rotation and expiration rules for machine credentials, and disable or delete identities that are inactive, orphaned, or no longer tied to a valid use case.
- Extend monitoring to NHI activity Log authentication events, privilege changes, and unusual access patterns for machine identities so that anomalous behaviour is visible during operations and audit review.
- Tie supplier offboarding to credential revocation When a vendor relationship ends or changes, revoke API keys, service account access, and integration tokens as part of the formal offboarding process.
Key takeaways
- ISO 27001 compliance is incomplete when service accounts, API keys, tokens, and certificates sit outside the same governance model used for human identities.
- The article's central risk is over-privileged, long-lived machine access that weakens auditability, expands blast radius, and complicates incident response.
- The control that changes the outcome is lifecycle governance: inventory, ownership, least privilege, rotation, monitoring, and revocation for every non-human identity.
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 and MITRE ATT&CK address the attack surface, NIST SP 800-53 Rev 5 sets the technical controls, and ISO/IEC 27001:2022 defines the regulatory obligations.
| Framework | Control / Reference | Relevance |
|---|---|---|
| OWASP Non-Human Identity Top 10 | NHI-05 — Overprivileged NHI | The article centres on machine identities carrying more access than their tasks require. |
| NHI-07 — Long-Lived Secrets | The article repeatedly warns about keys and tokens that remain valid beyond their intended use. | |
| NHI-01 — Improper Offboarding | Supplier access and inactive identities must be revoked as part of NHI lifecycle control. | |
| Recommendation — Review NHI permissions against task scope and remove excess access that increases audit and breach risk. Set expiry and rotation policies that prevent long-lived machine secrets from remaining active indefinitely. Revoke machine credentials during offboarding and disable orphaned identities before they become residual access. | ||
| NIST SP 800-53 Rev 5 | IA-5 — Authenticator Management | The article's secret rotation and credential storage guidance maps directly to authenticator lifecycle control. |
| AC-6 — Least Privilege | The article frames least privilege as the core access control principle for NHIs. | |
| Recommendation — Apply authenticator management to rotate, store, and revoke machine credentials on a defined schedule. Enforce least privilege for service accounts and API keys so each identity can only perform required actions. | ||
| ISO/IEC 27001:2022 | A.5.15 — Access control | ISO 27001 access control is the central compliance theme for NHI governance in this article. |
| A.8.24 — Use of cryptography | The article discusses encryption and secure storage of credentials as cryptographic control. | |
| A.5.19 — Information security in supplier relationships | Third-party API keys and service accounts are governed through supplier relationship controls. | |
| Recommendation — Document and enforce access rules for machine identities within your ISMS scope. Protect machine credentials with cryptographic controls and secure vaulting to reduce exposure. Include machine credentials in supplier controls and revoke them when the relationship changes. | ||
| MITRE ATT&CK | TA0006;TA0008 — Credential Access; Lateral Movement | Compromised machine identities can be used to access more systems and move through trusted environments. |
| Recommendation — Map compromised machine credentials to credential access and lateral movement detections in your monitoring pipeline. | ||
Key terms
- Non-Human Identity (NHI): A digital identity assigned to a non-human entity such as a software application, service account, API key, bot, machine, or AI agent that enables it to authenticate and interact with systems without direct human involvement. NHIs now outnumber human identities in most enterprises by 25 to 50 times.
- Service Account: A special-purpose account used by applications, automated tools, or services rather than a human user to interact with systems, APIs, and infrastructure. Service accounts are a primary category of NHI and one of the most frequently exploited attack vectors.
- Least Privilege: A security principle requiring that every identity, human or non-human, is granted only the minimum permissions necessary to perform its function. Least privilege is the single most effective control for reducing NHI blast radius.
- Secrets Lifecycle: Secrets lifecycle is the management of credentials from issuance through rotation, revocation, and offboarding. It matters because a secret that is technically valid can still be operationally unsafe if its owner, purpose, or downstream access paths are no longer current.
Deepen your knowledge
NHI governance, agentic AI identity, and machine identity lifecycle are core topics in our NHI Foundation Level course, the industry's only accredited NHI security programme. If you are building or maturing an IAM programme, it is worth exploring.
Published by the NHIMG editorial team on June 3, 2026.
Updated on October 6, 2026.
NHI Mgmt Group, the independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org