How should security teams deploy phishing-resistant passkeys in regulated environments without relying on a cloud identity provider?

Why This Matters for Security Teams

Passkeys remove password replay, but regulated environments still fail if authentication is outsourced to a cloud identity provider that cannot meet sovereignty, residency, or isolation requirements. The real issue is not the authenticator itself, but who controls registration, key binding, recovery, revocation, and audit evidence. NIST frames identity assurance as a governance problem as much as a technical one in the NIST Cybersecurity Framework 2.0, and that is especially true where auditability and local control are mandatory. NHIMG’s Ultimate Guide to NHIs shows how often identity failures come from weak ownership and poor lifecycle discipline, not just weak credentials. In regulated deployments, passkeys should reduce phishing risk without creating a new dependency chain that auditors cannot inspect or operators cannot recover. In practice, many security teams discover the cloud dependency problem only after an exception request, migration freeze, or regulator review has already exposed it.

How It Works in Practice

A regulated passkey deployment without a cloud identity provider usually means building a local trust boundary for the entire authentication lifecycle. The organisation keeps the relying party, user directory mapping, credential metadata, and audit logs under its own administrative control. That does not require abandoning phishing resistance; it requires changing where trust is anchored. A workable design typically includes:

• On-premises or privately hosted authenticating service with controlled data residency.
• Locally managed public key registration and attestation policy, with clear rules for which authenticators are allowed.
• Deterministic user-to-credential binding so auditors can trace each passkey to a specific account and device or authenticator event.
• Strong recovery workflows that do not quietly reintroduce password fallback as the primary escape hatch.
• Retention of authentication events, revocation actions, and administrative changes in systems the organisation can query directly.

Passkeys still rely on public key cryptography and phishing-resistant challenge-response flows, but the operational control plane matters just as much as the cryptography. NIST SP 800-53 Rev. 5 emphasises access enforcement, audit, and identity governance controls that map well to this model. For lifecycle discipline, NHIMG’s Lifecycle Processes for Managing NHIs is useful because the same discipline applies here: enrolment, rotation where applicable, revocation, and offboarding must be explicit and testable. The practical test is whether the organisation can prove who enrolled the passkey, who approved it, where the trust material lives, and how quickly it can be revoked. These controls tend to break down in federated enterprises with overlapping directories because identity ownership becomes ambiguous and recovery paths sprawl across teams.

Common Variations and Edge Cases

Tighter local control often increases operational overhead, requiring organisations to balance phishing resistance against admin burden and recovery complexity. That tradeoff is real in environments with contractors, distributed subsidiaries, or legacy applications that cannot speak modern FIDO workflows cleanly. Best practice is evolving, but there is no universal standard for how much attestation evidence or device binding is enough in every regulated sector. The most common edge case is fallback. If an organisation retains SMS, email links, or helpdesk-driven password resets as routine recovery paths, the passkey programme may improve day-to-day security while leaving the real attack surface intact. Another issue is cross-domain access: a local authenticator can be fully controlled, yet still fail compliance if downstream applications or session brokers outsource key audit functions. For teams evaluating broader identity risk, NHIMG’s 52 NHI Breaches Analysis reinforces a simple lesson: identity incidents usually follow weak lifecycle control, not just weak login methods. In some highly constrained environments, fully air-gapped authentication is feasible only with pre-provisioned hardware and tightly scripted recovery, which may slow helpdesk operations. The right answer is therefore not “cloud or passkeys,” but “local governance, verifiable logs, and narrowly bounded fallback paths.” When those pieces are missing, passkeys become a better front door on top of a fragile back door.

Related resources from NHI Mgmt Group

• How should security teams evaluate cloud identity tools in regulated environments?
• How should security teams reduce phishing risk in cloud identity environments?
• How should security teams unify identity across cloud and data center environments?
• How should security teams balance agility with identity control in cloud and AI environments?