How do passkeys fit into broader IAM and zero trust programmes?

Why This Matters for Security Teams

Passkeys improve the authentication step, but they do not complete the job of identity security. In a zero trust programme, the real question is not only “who authenticated?” but also “from what device, under what policy, and with what ongoing risk?” That is why passkeys need to sit inside a broader access architecture that includes device posture, session controls, revocation, and least privilege. NIST SP 800-207 Zero Trust Architecture makes this separation explicit: authentication is necessary, but continuous policy enforcement is what keeps access bounded.

This matters because security teams often treat passkeys as a replacement for passwords and then stop short of redesigning the rest of the access path. The result is better login assurance with the same old exposure in sessions, entitlements, and recovery workflows. NHI Management Group’s Ultimate Guide to NHIs — Standards notes that 90% of IT leaders say properly managing non-human identities is essential for a successful zero-trust implementation, which is a useful reminder that strong sign-in alone does not create zero trust.

In practice, many security teams discover the gap only after a passkey rollout leaves old recovery paths, broad application grants, or unmanaged devices still able to reach sensitive systems.

How It Works in Practice

Passkeys fit best as the primary human authentication method inside an IAM stack that evaluates more than the credential itself. A strong deployment ties passkey assurance to conditional access, device trust, application sensitivity, and session risk. The passkey proves the user has possession of the registered authenticator, but the platform still has to decide whether that user should receive access now, for this app, from this endpoint, and for how long.

That is why passkeys should be paired with zero trust controls rather than treated as a standalone control. In a mature model, the access request is evaluated at runtime against policy signals such as device health, phishing-resistant authentication status, geolocation, and privilege level. If the request is high risk, the system can step up assurance, narrow the session, or deny access entirely. The zero trust model in NIST SP 800-207 Zero Trust Architecture aligns well with this approach because it emphasises continuous verification rather than one-time trust.

Operationally, teams should think in layers:

• Use passkeys to reduce phishing and credential replay at sign-in.
• Bind access decisions to device posture and application context.
• Limit sessions with short duration, re-authentication, and token revocation.
• Keep recovery workflows stronger than legacy password reset paths.
• Apply privileged access management for admin and sensitive workflows.

For broader identity governance, the same principle applies to service accounts and machine access, where Guide to SPIFFE and SPIRE shows how workload identity can be treated as a cryptographic primitive rather than a shared secret. Current guidance suggests passkeys strengthen the human edge of IAM, but they do not remove the need for entitlement review, continuous authorization, or session-level controls. These controls tend to break down when legacy applications cannot consume modern identity signals because the organisation falls back to static allowlists and long-lived sessions.

Common Variations and Edge Cases

Tighter authentication usually improves security, but it also increases operational friction, so organisations have to balance user experience against control depth. That tradeoff is especially visible when passkeys are introduced into hybrid estates, shared workstations, or high-assurance administrative paths.

One common edge case is legacy applications that support modern login but not modern session governance. In that environment, passkeys may be used for sign-in while the downstream app still depends on long-lived tokens, weak logout behaviour, or coarse role mapping. Another is step-up access: passkeys can satisfy the primary auth requirement, yet zero trust may still require a second factor, a managed device, or a fresh policy decision for sensitive transactions. Best practice is evolving here, and there is no universal standard for every recovery or step-up flow.

A second issue is the assumption that passkeys eliminate phishing risk everywhere. They substantially reduce phishing for the authenticated step, but they do not stop social engineering of help desks, device compromise, or over-permissioned sessions. That is why broader governance remains necessary. The NHI Management Group research on Ultimate Guide to NHIs — Standards also highlights how pervasive excessive privilege remains, which is a useful warning that stronger login assurance cannot compensate for poor entitlement hygiene.

Where organisations have BYOD, contractor access, or shared devices, passkeys should be paired with device trust controls and tightly scoped sessions, otherwise the authentication gain can be diluted by weak endpoint governance.

Related resources from NHI Mgmt Group

• Why does vendor access weaken zero trust programmes in practice?
• How should security teams modernize access reviews in zero trust programmes?
• Why do non-human identities complicate zero trust architecture?
• Why do non-human identities increase zero trust risk?