Glossary¶

Short definitions of the terms used across these docs, with links to where each one is explained in full. Concepts introduces the core ideas in order.

Product terms¶

Active check: A check that writes or runs something to test a control, rather than only reading configuration. Examples are the bootstrap write probes and the Nitro host checks that run commands over SSM. untrust scan --read-only skips them. See Scan a deployment.
Assurance: A label on some results that says how strong a pass is: report-derived, probed or operator-declared. See Verdicts.
Attack path: A chain of failing checks that together let an attacker reach a secret or a workload. The console shows them next to the findings.
CI binding: A registered trust between your organization and one CI pipeline. The pipeline authenticates uploads with its CI provider's OIDC token, and the binding pins which repository, project, branch and workflow may use it. See Send evidence from CI.
Collector: The untrust collector agent on a confidential host. It reports hardware evidence on a schedule, outbound only, signed with a key it created on the host. See Enroll a collector.
Coverage: What a scan or rule pack was able to assess, compared with what it would assess given every input. A check that was skipped or errored lowers coverage; it is never counted as passing.
Decided / observed: A release decision untrust made through untrust release verify is decided. A release untrust only found in a cloud log is observed.
Detection: A rule that matches events in cloud audit logs or collector reports, such as a key released to an unexpected image. See Runtime detections and the detection rules.
Evidence: What a verdict is based on: a scan report, a build or IaC receipt, a collector bundle, detection events or a release decision. See Evidence.
Evidence pack: A signed bundle of evidence and results for an auditor or relying party, which can be checked offline with untrust pack verify. See Verify evidence offline.
Finding: One check or rule result on one target.
Fleet: A group of confidential hosts of one platform, with a shared policy for measurements and minimum firmware levels.
Issue: One or more findings grouped in the console, with an owner and a status.
Ledger: The append-only, hash-chained record of key-release decisions. Checked offline with untrust ledger verify.
Organization: Your tenant in the hosted console. Everything belongs to exactly one organization.
Policy: A statement of what must be true, checked by rules across lifecycle stages. A policy is enforced, partial or failing. Some policies are release gates. See the policy catalogue.
Project: A group of resources inside an organization, which can limit which members see what.
Receipt: The record a CI gate (untrust buildscan, untrust iacscan) or a release decision produces. A CI receipt is an authenticated submission, not a verified attestation.
Release gate: A policy that must be enforced before untrust allows a key release.
Stale: A collector host that has stopped reporting. Its last result is never shown as current.
Unknown: The console's word for a result that was not assessed (SKIP or ERROR).
Verdict: The result of one check: PASS, FAIL, SKIP or ERROR. Only PASS and FAIL are assessed. See Verdicts.

Confidential computing terms¶

Attestation: A signed statement from the hardware of what was measured when a TEE launched. See Attestation.
Attestation document: The attestation format of AWS Nitro Enclaves: a COSE-signed document carrying PCR values and optional user data, nonce and public key.
Confidential Space: Google Cloud's managed environment that runs a container image in a Confidential VM and issues an attestation token for it.
Confidential VM (CVM): A virtual machine whose memory is protected from the host by hardware such as AMD SEV-SNP or Intel TDX.
Debug mode: A TEE launch mode that lets the host inspect the TEE. A debug TEE gives no confidentiality, so production policies forbid it.
Key broker (KBS): The service that releases a secret to a workload after checking its attestation. It can ask untrust for a decision with untrust release verify.
Measurement: A hash of what the TEE launched: firmware, kernel, image or configuration. Comparing measurements with expected values shows what code is running.
Microsoft Azure Attestation (MAA): Azure's attestation service. It issues tokens that Azure Key Vault's Secure Key Release policies trust.
Nonce: A fresh value the relying party puts into an attestation request so an old attestation can't be replayed.
PCR: Platform Configuration Register. A slot holding a measurement. Nitro Enclaves use PCR0 to PCR8; PCR8 holds the hash of the certificate that signed the enclave image.
Reference integrity manifest (RIM): NVIDIA's signed list of expected GPU firmware and driver measurements.
Relying party: Whoever decides to trust a TEE based on its attestation, usually a key broker.
Secure Key Release (SKR): Azure Key Vault's feature that releases a key only when the caller presents an attestation token meeting the key's release policy.
TCB: Trusted computing base. In attestation, the TCB level is the firmware and microcode version the hardware reports; a fleet can require a minimum.
TEE: Trusted execution environment: hardware-isolated memory the host, hypervisor and cloud operator cannot read. See TEEs.
vTPM: A virtual Trusted Platform Module that records a VM's boot measurements.
Workload Identity Federation (WIF): Google Cloud's way of exchanging an external token, such as a Confidential Space attestation token, for Google credentials. Its provider conditions decide which workloads can decrypt a Cloud KMS key.
Wrap key: The public key a workload puts in its attestation so the key broker can encrypt the released secret to it, and only that workload can unwrap it.