What are the main implementation gaps in secure remote signing under eIDAS?

The main gap is proving sole control of the signature process in a secure environment. The article notes that earlier eIDAS rules did not clearly specify how a user should authenticate securely to a signing service provider, especially when signing devices are operated remotely. That creates uncertainty around authentication assurance, device handling, and the trust model for qualified signature creation.

Where the implementation gap sits in remote qualified signing

The practical gap is not whether eIDAS recognises electronic signatures, it is how a provider proves the signer had sole control of the signing process when the signing operation happens remotely. That question becomes harder when the user and the signature-creation device are separated, because assurance depends on the remote authentication flow, device custody assumptions, and the trust boundary between the user, the service, and the qualified trust service provider.

One reason this remains difficult is that “secure remote signing” is an architectural pattern, not a single control. It has to preserve signer intent, prevent unauthorised signing, and avoid weak remote approval flows that reduce the evidential value of the qualified signature. For background on the identity and secret-management side of these assurance problems, NHIMG’s Ultimate Guide to NHIs — What are Non-Human Identities is useful because it frames how credentials, tokens, certificates and related trust material are governed when they are the mechanism of access.

The other core gap is that the trust model for remote signing has to be explicit enough to withstand challenge. If the signing service is allowed to mediate authentication, authorisation, and key use, then the implementation must show what evidence ties the action to the right person, at the right time, under the right conditions. That is why remote signing discussions quickly become questions about assurance level, device binding, session control, and the handling of signing keys or signing operations outside the user’s immediate control.

Why the missing detail matters for assurance and interoperability

When the rules do not clearly specify the secure-authentication model, providers can implement materially different experiences while still claiming compliance. In practice, that creates interoperability friction, because relying parties may not know whether a remote signature was protected by strong cryptographic proofing, a weaker application login, or a delegated approval process that is easy to misuse. The result is not only technical inconsistency, but also uncertainty about whether the signature can be trusted for high-value transactions.

This is especially sensitive where the signing process depends on a remotely operated device or signing service rather than a locally controlled qualified signature creation device. A remote design can be secure, but only if the control model is tight enough to prevent impersonation, replay, or unauthorised initiation. NHIMG’s Ultimate Guide to NHIs — Key Challenges and Risks is relevant here because the same operational patterns, visibility gaps, and credential control failures that weaken machine trust can also weaken the assurance story around remote signing.

eIDAS also exposes a governance gap: the framework sets the legal and trust-service context, but implementations still need a concrete engineering standard for how strong authentication, device binding, and auditability are enforced. If those elements are left to vendor interpretation, organisations may end up with signatures that are legally framed as qualified but operationally harder to defend in audits, disputes, or cross-border acceptance scenarios.

What practitioners should verify before treating remote signing as secure

Practitioners should focus on the evidence chain, not the label. The key question is whether the provider can show that the signer was strongly authenticated, that the signing event was initiated intentionally, and that the signing key or signing action was protected from misuse throughout the transaction. For a useful control lens on verification and lifecycle discipline, NHIMG’s Ultimate Guide to NHIs — Key Research and Survey Results provides a grounded way to think about how identity-related gaps persist when governance is weak or incomplete.

Verify the exact authentication factors used for signing, and whether they are resistant to phishing, replay, and session hijack.
Verify who controls the signing device or signing module at the moment of signature creation, especially in hosted or mobile remote-signing flows.
Verify the audit trail for initiation, approval, cryptographic use, and timestamping, so disputes can be reconstructed.
Verify exception handling for recovery, revocation, and account compromise, because remote signing is only as strong as its revocation path.

Practitioner takeaway: The critical implementation question is not whether remote signing is convenient, but whether the provider can prove strong signer authentication and sole control with evidence that survives legal and operational scrutiny.

Risk and Threat Considerations

Remote signing concentrates trust into a smaller number of systems, which means a weak authentication design or poorly governed signing workflow can turn into unauthorised signature creation, repudiation disputes, or broad trust failure across many transactions. The risk is highest when the signing service can be reached through generic login flows, shared devices, or ambiguous delegation rules.

Failure mechanism: An attacker, or simply an over-permissive workflow, exploits weak remote authentication or session control to trigger a signature without true sole control by the signer.

Impact: The organisation may issue signatures that are difficult to defend as qualified, weaken non-repudiation, and expose regulated transactions to challenge, rejection, or legal dispute.

Standards & Framework Alignment

This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.

CIS Controls v8, NIST CSF 2.0, NIST Zero Trust (SP 800-207) and NIST SP 800-63 set the technical controls, while NIS2 define the regulatory obligations.

Framework	Control / Reference	Relevance
NIS2	Operational Security and Incident Handling	Remote signing failures can create regulated service disruption and trust exposure.
Recommendation — Document signing-service controls, monitoring, and incident response for authentication or key compromise.
CIS Controls v8	6 — Access Control Management	Remote signing depends on strong access control and restricted signing authority.
	8 — Audit Log Management	Remote signing needs evidence of who initiated and completed each signing action.
Recommendation — Enforce least-privilege access to signing services and revoke unused signing paths quickly. Log authentication, approval, and signature-creation events with tamper-resistant retention.
NIST CSF 2.0	PR.AA — Identity Management, Authentication and Access Control	The core gap is proving authenticated signer control in a remote trust model.
	GV.OV — Cybersecurity Risk Management Strategy	eIDAS remote signing needs a defensible governance model for assurance and trust.
Recommendation — Strengthen remote signer authentication and bind approval steps to the signing event. Define assurance thresholds and accept only remote-signing designs that meet them.
NIST Zero Trust (SP 800-207)	PL-1 — Policy and Access Enforcement	Remote signing needs explicit policy enforcement around who may trigger a signing action.
Recommendation — Enforce policy-based access decisions for remote signing and protect the signing path.
NIST SP 800-63	IAL — Identity Assurance Level	The question turns on how strongly the signer is authenticated before remote signing.
Recommendation — Map remote-signing flows to an assurance level that matches the transaction risk.

Practitioner Guidance

What to verify: Require a documented control narrative that links the signer, the authentication event, the signing action, and the protected key or device path. If any one of those links is missing, the implementation is not yet strong enough to rely on for high-assurance signing.

Decision rule: If the remote flow cannot demonstrate sole control and strong signer-bound authentication, treat it as a lower-assurance signature process even if the vendor markets it as “qualified” or “secure”.

Practitioner takeaway: The right standard is evidential assurance, not product branding, and remote signing should only be accepted when the control model is explicit, testable, and independently defensible.