Zero trust depends on identity and access management discipline

At a glance

What this is: This is an analysis of why zero trust architectures still depend on identity and access management as the enforcement layer.

Why it matters: For IAM and NHI practitioners, it reinforces that zero trust fails when identity, authorization, and access review are treated as separate chores.

By the numbers:

• 90% of IT leaders say properly managing NHIs is essential for a successful zero-trust implementation.
• 97% of NHIs carry excessive privileges, increasing unauthorised access and broadening the attack surface.
• Only 5.7% of organisations have full visibility into their service accounts.

👉 Read StrongDM's analysis of why zero trust depends on identity and access management

Context

Zero trust is a governance model, not a product category. It assumes every request must be authenticated, authorized, and revalidated, which means identity and access management becomes the mechanism that turns the model into enforcement. For NHI governance, the same logic applies to service accounts, API keys, tokens, certificates, and AI agents because each one acts with execution authority.

The article’s core claim is straightforward: you cannot claim zero trust while allowing access to drift, remain unreviewed, or depend on manually managed roles. That matters because NHI populations expand faster than human identities, and unmanaged machine access can undermine zero trust even when human controls look mature. This is a typical control gap, not an edge case.

Key questions

Q: How should security teams apply zero trust to non-human identities?

A: Security teams should apply zero trust to non-human identities by requiring explicit ownership, least-privilege access, short-lived credentials, and continuous validation. Treat service accounts, API keys, tokens, and certificates as active identities, not static infrastructure. If a machine identity can act indefinitely or across too many systems, zero trust is not actually enforced.

Q: What is the difference between zero trust and least privilege in IAM?

A: Zero trust is the operating model that continuously verifies identity and context. Least privilege is the access principle that limits what an identity can do. In practice, zero trust uses least privilege as one of its controls, but also needs ongoing reauthentication, revocation, and monitoring to keep access decisions current.

Q: When do non-human identities create the most risk for zero trust programs?

A: Non-human identities create the most risk when they have broad, persistent, or poorly owned access. That usually happens in pipelines, integrations, shared automation, and service accounts that are granted more rights than they need. Zero trust programs struggle most when those identities are not tracked, rotated, or reviewed with the same discipline as human accounts.

Q: Why do machine identities complicate zero trust architecture?

A: Machine identities complicate zero trust architecture because they do not behave like people. They authenticate at scale, often without interactive prompts, and they can hold access across many systems for long periods. That makes ownership, session control, and revocation more important, because the usual human-centric identity signals are weaker or absent.

Technical breakdown

Why zero trust still depends on identity verification

Zero trust does not remove identity from the architecture. It shifts the decision point to every request, where the system evaluates who or what is asking, what it is allowed to do, and whether the context still supports access. Authentication establishes identity proof, authorization sets the allowed action, and continuous validation checks whether trust should persist. In NHI environments, this becomes harder because service identities often lack interactive users, obvious ownership, or natural reauthentication events. The result is that access rules must be explicit, time-bound where possible, and tied to a control plane that can observe machine identity behavior. Practical implication: treat identity proof and authorization as runtime controls, not one-time onboarding steps.

Practical implication: move zero trust checks into runtime access decisions for both human and non-human identities.

Least privilege and role design for NHIs

Least privilege is the operational core of zero trust, but NHIs rarely fit clean role boundaries. Service accounts and API keys often accumulate permissions because they support multiple automation paths, shared pipelines, or legacy dependencies. That creates identity blast radius, where a single compromised credential can reach far more than intended. Role-based access control can help, but only if roles are narrow enough to match actual task scope and are reviewed against real system use. Attribute-based policies can add context, such as environment, workload, or time, which is useful when identities are ephemeral or distributed. Practical implication: map each NHI to a bounded task and remove permissions that are only convenient, not necessary.

Practical implication: redesign NHI roles around task scope, not team convenience or historical access patterns.

Continuous validation is the difference between policy and trust

Zero trust fails when access decisions are static. Continuous validation means permissions, session context, and identity signals are rechecked as conditions change. For humans, that can mean step-up authentication or session renewal. For NHIs, it often means credential rotation, token TTL enforcement, workload attestation, and access revocation when the workload no longer matches policy. The architecture matters because machine identities can operate at high speed and high scale, making stale permissions dangerous for longer than teams expect. This is where NHI governance overlaps with zero trust most directly: if an identity can act indefinitely, trust has become standing privilege. Practical implication: enforce short-lived credentials and automated revocation paths wherever machine access is granted.

Practical implication: make credential lifetime and revocation automation part of zero trust enforcement, not an adjacent task.

Breaches seen in the wild

• Moltbook AI agent keys breach — Moltbook breach exposed 1.5M AI agent keys.
• Sisense breach — unauthorized GitLab access led to exfiltration of access tokens, API keys and certificates.

Read our 52 NHI Breaches Analysis report for a comprehensive view of breaches impacting Non-Human Identities including AI Agents.

NHI Mgmt Group analysis

Zero trust without identity governance is a policy statement, not an operating model. The article correctly centers identity and access management because zero trust needs a decision engine, not a slogan. In practice, that decision engine must cover human users, service accounts, tokens, and automation pathways with equal rigor. If identity review is incomplete, the architecture may look segmented while privileged access remains broadly reachable. Practitioners should treat identity governance as the control plane of zero trust.

NHI sprawl is the hidden reason many zero trust programs stall. Human identity controls often improve first, while machine identities continue to accumulate permissions in pipelines, integrations, and admin workflows. That creates a governance asymmetry that zero trust frameworks do not tolerate for long. The field needs to stop treating NHIs as exceptions and start treating them as the dominant access population in modern environments. Practitioners should inventory machine identities before they attempt broader zero trust expansion.

Least privilege has to become measurable, or it will stay aspirational. The post implicitly points to a familiar gap: teams say they are pursuing least privilege, but they rarely can prove that access is bounded to task, time, and context. Without measurement, access creep becomes invisible until a credential is abused. Zero trust programs need entitlement review, rotation discipline, and revocation evidence as baseline metrics. Practitioners should define what acceptable privilege looks like and monitor drift against it.

Identity blast radius is the right concept for evaluating zero trust readiness. A system can authenticate correctly and still be unsafe if one credential opens too many paths. That is especially true for NHIs, which often sit inside deployment systems, cloud tooling, and service-to-service workflows. Zero trust should be judged by how far a compromised identity can move, not only by whether login gates exist. Practitioners should assess blast radius before assuming policy coverage equals resilience.

From our research:

• 90% of IT leaders say properly managing NHIs is essential for a successful zero-trust implementation, according to the Ultimate Guide to NHIs.
• Only 5.7% of organisations have full visibility into their service accounts, which means many zero trust programs start without a complete access inventory.
• For the broader control model, see Ultimate Guide to NHIs , Standards for the framework mappings that support identity-led enforcement.

What this signals

Identity governance will increasingly be the gating function for zero trust, not an adjacent programme. As environments add more automation, the practical boundary of zero trust shifts from network segmentation to access ownership and entitlement quality. Teams that cannot map non-human identities to owners and purposes will find policy coverage harder to defend in audits or incident reviews. NHI Lifecycle Management Guide

The deeper signal is that zero trust maturity now depends on how well organisations manage machine access drift. Our research shows 97% of NHIs carry excessive privileges, which means the programme risk is less about adoption and more about entitlement hygiene. Aligning with NIST SP 800-207 Zero Trust Architecture is necessary, but it is not sufficient without operational NHI controls.

For practitioners

• Map NHI ownership to every access path Create an inventory that links each service account, token, certificate, and automation identity to an accountable owner and a defined business purpose. Include third-party and pipeline identities, because zero trust cannot be enforced where ownership is unknown.
• Enforce short-lived credentials and rotation Replace long-lived secrets with short-lived credentials where possible, and require automated rotation for everything that cannot be eliminated. Track rotation exceptions separately so dormant access does not hide inside normal operations.
• Review roles against real task scope Compare current entitlements to actual workload behavior and remove permissions that are inherited, duplicated, or only used for convenience. Use role reviews to shrink standing access before layering on more policy checks.
• Tie access approval to validation evidence Require evidence of authentication strength, policy checks, and revocation paths before granting machine access to sensitive systems. In zero trust terms, approval without continuous validation is just a deferred risk.
• Measure identity blast radius quarterly Test how far a compromised non-human identity could move across environments, pipelines, and data stores. Use those results to prioritize remediation where one credential can still reach too many systems.

Key takeaways

• Zero trust only works when identity and access management is the enforcement layer, not a supporting control.
• Non-human identities are now a primary source of zero trust failure when ownership, privilege, and validation are incomplete.
• Practitioners should measure access drift, rotation discipline, and identity blast radius before claiming zero trust maturity.

Key terms

• Zero Trust Architecture: A security model that assumes no request is trusted by default, even inside the network. Access is granted only after continuous verification of identity, context, and policy. In practice, it requires identity-led controls that can keep pace with changing risk.
• Non-Human Identity: A non-human identity is any machine or software identity that can authenticate and act in an environment, including service accounts, API keys, tokens, certificates, bots, workloads, and AI agents. These identities often outnumber human users and can create large blast radius when over-privileged.
• Least Privilege: Least privilege means giving an identity only the access needed to complete a specific task, nothing more. For NHIs, that includes limiting scope, duration, and reachable systems so a compromised credential cannot move broadly across the environment.
• Identity Blast Radius: Identity blast radius is the amount of damage one compromised identity can cause before it is detected and contained. It is shaped by privilege breadth, token lifetime, ownership quality, and how many systems a single non-human identity can reach.

Deepen your knowledge

Zero trust identity governance is a core topic in our NHI Foundation Level course, the industry's only accredited NHI security programme. If you are extending zero trust into machine access, it is worth exploring.

This post draws on content published by StrongDM: You Can't Have Zero Trust Without Identity & Access Management. Read the original.