They often treat external users as exceptions and manage them in local application silos. That leads to inconsistent entitlements, weak segregation of duties, and poor accountability. External identities are not edge cases in manufacturing. They are part of core operations and need one governance model that spans the ecosystem.
Why This Matters for Security Teams
Manufacturers often assume external identities belong in procurement, partner portals, or local application admin lists. That framing breaks down because suppliers, contractors, integrators, logistics partners, and service vendors routinely touch production systems, OT-adjacent tools, and shared SaaS workflows. When those identities are governed application by application, security teams lose a consistent view of who should have access, why they have it, and when it should be removed.
The result is not just excess access. It is weak segregation of duties, inconsistent approvals, poor revocation hygiene, and limited auditability across the ecosystem. NHIMG research on the State of Non-Human Identity Security shows that lack of credential rotation and over-privileged accounts are leading attack factors, which is relevant because external users often inherit the same lifecycle weaknesses as other NHIs. NIST’s Cybersecurity Framework 2.0 reinforces the need for repeatable governance, not ad hoc exception handling.
Manufacturing teams usually notice the governance gap only after a supplier account is still active long after a project ends, rather than through deliberate identity lifecycle design.
How It Works in Practice
Effective external identity governance in manufacturing starts by treating every non-employee identity as part of a single control plane, even when access spans ERP, MES, PLM, ticketing, remote support, and data exchange platforms. That means one authoritative process for onboarding, approval, role definition, evidence collection, periodic review, and deprovisioning across the ecosystem. The governance model should define identity ownership, business sponsorship, access purpose, and expiry by default.
In practice, that requires more than directory cleanup. Security teams need joiner-mover-leaver workflows that are tied to contract events, project milestones, and vendor service windows. Access should be granted through standard roles or attribute-based policies where possible, with exception handling reserved for narrowly justified cases. For shared services and machine-to-machine access, the same discipline should extend to secrets and service accounts, because external operators often use both human and non-human paths.
NHIMG’s Ultimate Guide to NHIs emphasises lifecycle control as the backbone of NHI governance, while the Top 10 NHI Issues highlights what happens when rotation, monitoring, and revocation are inconsistent. For manufacturers, the practical control pattern is simple:
- Assign a named business owner for every external identity or partner group.
- Use time-bound access with automatic expiry for projects, support windows, and seasonal work.
- Review access centrally across applications, not by system owner preference.
- Revoke access and secrets immediately when contracts, incidents, or roles change.
This guidance breaks down when factories rely on local plant-level exceptions and disconnected legacy systems, because central review cannot fully see or remove access that bypasses the enterprise identity model.
Common Variations and Edge Cases
Tighter external identity control often increases operational overhead, requiring organisations to balance faster partner onboarding against stronger governance and auditability. That tradeoff is real in manufacturing, where maintenance vendors, OEMs, and seasonal integrators may need rapid access to keep production moving.
Best practice is evolving for environments that mix IT, OT, and third-party service access. There is no universal standard for every edge case yet, so manufacturers should classify external identities by risk and criticality rather than forcing all partners into the same approval path. A low-risk document portal user should not follow the same control pattern as a remote technician with access to plant-support tooling.
One common failure mode is treating a partner company as a single trusted entity. In reality, each named user, delegated admin, subcontractor, and service account needs its own accountability trail. Another is assuming that SSO alone solves governance. SSO improves authentication, but it does not replace entitlement review, SoD analysis, or timely revocation. The 52 NHI Breaches Analysis is useful here because it shows how credential and access control failures compound when identity ownership is unclear. Where partner ecosystems are large, the most mature programmes also align with regulatory and audit perspectives so evidence can be produced without manual reconciliation.
Manufacturers usually get this wrong in the middle ground, where access is important enough to be dangerous but not visible enough to trigger formal governance until after an audit finding or supplier incident.
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 and NIST AI RMF set the governance and control requirements practitioners need to meet.
| Framework | Control / Reference | Relevance |
|---|---|---|
| NIST CSF 2.0 | PR.AC-4 | External identities need centrally managed access and least privilege across the ecosystem. |
| OWASP Non-Human Identity Top 10 | NHI-03 | Lifecycle control applies to external users and their secrets, not just employees. |
| NIST AI RMF | Governance should establish accountability and oversight for identity-related decisions. |
Define and review external access centrally, then remove entitlements when business need ends.
Related resources from NHI Mgmt Group
Deepen Your Knowledge
Reviewed and updated by the NHIMG editorial team on July 8, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org
