Why do digital credentials matter if passkeys already improve authentication?

Why This Matters for Security Teams

Passkeys improve how people sign in, but they do not answer the harder question many services face: what, exactly, is being proven? Digital credentials are about verified claims, not just successful authentication. If a workflow needs to confirm age, licence status, training completion, or prior vetting, a passkey alone cannot supply that assurance. Current identity guidance in NIST SP 800-63 Digital Identity Guidelines draws this distinction clearly: authentication establishes an identity event, while credentials can carry attributes from a trusted issuer.

This gap matters because security teams often overestimate the coverage of phishing-resistant login and then bolt on manual checks later. That creates inconsistency, user friction, and weak auditability. In NHI-heavy environments, the same pattern shows up as secret sprawl and uncontrolled trust chains, which is why NHIMG research on the Guide to the Secret Sprawl Challenge and the Ultimate Guide to NHIs keeps pointing back to the same operational reality: proof of possession is not proof of qualification. In practice, many security teams encounter credential misuse only after access has already been granted on the wrong basis.

How It Works in Practice

Digital credentials add a verifiable claim layer on top of authentication. A passkey can tell a service that the same device and user completed a challenge, but a digital credential can also prove a statement issued by a trusted authority. That statement might be “over 18,” “licensed practitioner,” “employee in good standing,” or “completed KYC.” The issuer signs the credential, the verifier checks the signature and trust chain, and the subject presents only the minimum necessary data.

In practice, this is most useful when services need selective disclosure and stronger auditability than password resets or profile fields can provide. A common pattern is:

• Authenticate with a passkey or other phishing-resistant method.
• Present a digital credential from a trusted issuer.
• Verify cryptographic integrity, expiry, and revocation status.
• Release only the required attribute, not the full identity record.

That design separates “who is at the keyboard” from “what is true about them,” which is important in regulated onboarding, access approvals, benefits eligibility, and cross-organisation trust. NIST’s identity guidance and the OWASP Non-Human Identity Top 10 both reinforce a broader lesson: trust decisions should be explicit, bounded, and revocable, not inferred from a single login event. For operational teams, NHIMG’s 2024 Non-Human Identity Security Report is useful context because it shows how often organisations still rely on insecure sharing and static access patterns rather than dynamic proof. These controls tend to break down when the issuer trust model is unclear, because verifiers cannot reliably distinguish a genuine credential from a merely valid-looking token.

Common Variations and Edge Cases

Tighter credential checks often increase issuance, recovery, and privacy overhead, requiring organisations to balance stronger proof against user friction and support cost. That tradeoff is why guidance here is still evolving rather than settled. Some environments only need passkey-based authentication plus account-level policy, while others need attribute credentials with revocation and selective disclosure.

There are also practical exceptions. A digital credential is not always the right answer if the attribute changes too frequently, if the issuer cannot be trusted, or if the verifier cannot maintain revocation checks. In those cases, current guidance suggests using a live authorisation lookup or an external source-of-truth instead of embedding the claim in a reusable credential. For example, employment status may be better checked from an HR system, while age verification may fit a portable credential issued once and reused across services.

Security teams should also separate person credentials from workload identity. Passkeys and digital credentials solve human-facing proof, but they do not replace NHI controls for services, APIs, and autonomous systems. NHIMG’s research on the CI/CD pipeline exploitation case study and broader secret-sprawl patterns shows how quickly trust collapses when identity assertions are reused outside their intended scope. The right control depends on the question being asked: authentication, attestation, or ongoing authorisation are not interchangeable.

Related resources from NHI Mgmt Group

• What controls matter most for legally defensible digital signatures?
• Why do dashboards matter in NHI governance?
• Why do application testing tools matter for NHI governance?
• Why do Shai Hulud style attacks matter to NHI governance?