Require TPM key attestation for hardware-bound certificate issuance

Frame this document as a source-led configuration and assurance check: Require TPM key attestation for hardware-bound certificate issuance. Only the official source and traced locations below supply facts. Confirm applicability before acting.

Source fact:

The official TPM Key Attestation from Microsoft supports the following bounded statements:

• TPM key attestation lets a certificate requester prove cryptographically that the requested RSA key is protected by a trusted TPM. The research record locates this support at Section: TPM key attestation.
• TPM-attested keys provide nonexportability, anti-hammering, and hardware isolation assurances. The research record locates this support at Section: Why is TPM key attestation important?.

Keep the evidence boundary at these traced claims. They support a review of forests, domains, controllers, directory partitions, trusts, sites, replication links, service accounts, and delegated roles; they do not support conclusions outside the source’s stated conditions.

What the source does not establish

Attestation requires a designed CA trust model and compatible certificate templates; it is not a generic TPM-health signal. The citation is not a substitute for observed state, authorization, compliance evidence, or dependency health. Examine Windows DNS, time synchronization, network reachability, PKI, backups, virtualization safeguards, and privileged identity before translating the source into an operational decision.

Applicability questions

• For source statement 1 at Section: TPM key attestation, which observable configuration, record, or test can confirm applicability here?
• For source statement 2 at Section: Why is TPM key attestation important?, which observable configuration, record, or test can confirm applicability here?
• What inventory proves which parts of forests, domains, controllers, directory partitions, trusts, sites, replication links, service accounts, and delegated roles are in and out of scope?
• Which condition in Windows DNS, time synchronization, network reachability, PKI, backups, virtualization safeguards, and privileged identity must be healthy before evidence is trustworthy?
• What result would disprove the working assumption and return the issue to the owner?

DSE recommendation:

DSE recommends using the cited source as the evidence anchor for this decision. Anchor the review in the cited section and keep observation separate from interpretation. Record the source location, examined part of forests, domains, controllers, directory partitions, trusts, sites, replication links, service accounts, and delegated roles, observed and expected states, owner, and reason for deviation.

Do not move from citation to production in one step. Pilot the decision where practical, observe agreed signals, retain a reversal point, and verify Windows DNS, time synchronization, network reachability, PKI, backups, virtualization safeguards, and privileged identity. Handle credentials, keys, recovery data, and personal information through approved secure channels.

Verification and evidence

A reviewer should be able to retrace the decision from Section: TPM key attestation; Section: Why is TPM key attestation important? through directory and policy exports, replication and locator tests, event logs, trust state, role ownership, and controlled authentication tests. Record what was collected, where, when, by whom, and which system or role it represents.

Preserve both successful and failed observations, along with approval and rollback evidence. Avoid uncontrolled production experiments. Assign an expiry or event-driven recheck so the conclusion is not treated as permanent.

Official references

• TPM Key Attestation — Microsoft