Trust & Threat Model#

In practice, the parties don’t need unrestricted review of each other’s proprietary source code before reaching agreement. They agree on signed artifacts, measured builds, allowed network paths, logging rules, attestation evidence, and the key-release policy that ties them all together. High-assurance deployments — especially anywhere code handles customer payloads — may still call for source review, third-party audit, SBOM review, or reproducible-build evidence.

The model provider distributes encrypted model artifacts and defines a policy that allows secure key distribution with successful attestation evidence. A key-management authority implements the policy and releases model keys only to workloads that present valid attestation evidence matching that policy. The enterprise data owner controls which inputs are sent into the attested workload, where outputs are delivered, and how outputs and logs are retained.

Figure 4 maps those responsibilities to administrative domains.

_images/cvm-trust-and-responsibility-model.png

Figure 4 Confidential VM Trust and Responsibility Model#

Table 4: Confidential VM Trust and Responsibility Model

Figure step

Diagram element

What it means

1

Model release policy

Model owner defines approved measurements and release conditions.

2

Enterprise data policy

Enterprise data owner controls callers, input/output paths, egress, logs, and retention.

3

Assurance authority

Key-release authority owns reference values, collateral, and release audit.

4

CVM platform operation

OEM or platform operator provides host firmware, KVM/QEMU, OVMF, GPU assignment, and runbooks.

5

Model-key gate

Model weights become readable only inside the measured confidential workload and protected GPU session.

6

Request path

Enterprise requests traverse approved gateway, CVM endpoint, and network controls.

7

Assurance gate

Evidence verification and key release replace direct platform trust.

The different personas in the end to end deployment are trusted and untrusted with different artifacts in this deployment allowing a clean separation of ownership and access while all personas are outside the trust boundary of the execution environment where the AI model runs and data is provided to it. The following table explains the controls, trust each persona has:

Table 5: Persona Trust and Controls

Party

Owns or controls

Trusted for

Not trusted with

Model provider

Model weights, guest image contents, artifact encryption, model-key release policy

Defining the approved workload and protecting model IP

Access to enterprise infrastructure, persistent data stores, or operational logs

Enterprise data owner

Data-handling policy, approved users, retention policy, business risk acceptance

Defining what data may enter the service and what operational data may be logged or retained

Unencrypted model weights, model keys, or model internals

Platform operator

Bare-metal host, firmware rollout, CVM launch environment, networking, storage, monitoring, capacity, incident response

Availability, correct launch mechanics, and approved platform operation

Unencrypted model weights, model keys, or decrypted runtime memory

CC software provider

Guest image bootstrap, attestation client, measurement tooling, GPU CC enablement, image-build validation tooling, support matrix, failure signals

Correct confidential-computing implementation, verifiable measurements, patching, and key-release enforcement

Production model keys unless explicitly operating a trusted key-release service

Application or agent developer

Gateway, application logic, user experience, prompt handling, authorization, retention controls

Implementing application behavior, authorization, and logging under enterprise data policy

Model-provider keys or unencrypted model weights

Key-release authority

Reference values, verifier policy, key-release policy, KMS/HSM configuration

Correct policy enforcement and audit

Host or VM administration by default

End user

Prompts, files, audio, images, or other inputs

Supplying authorized inputs to approved application endpoints

Model internals or administrative control

What this protects against: a host admin reading guest memory, an attacker pulling unencrypted weights off disk, key extraction from standard VM secret stores, and standard debugging or administrative tools attached to the confidential workload. More broadly, anyone with privileged infrastructure access — host, hypervisor, storage, network, datacenter, support — shouldn’t be able to see model weights, model keys, or decrypted runtime memory through normal platform control.

What it doesn’t: a malicious guest image supplied by the model provider, vulnerable inference code inside the CVM, payload logging by the application itself, a compromised attestation or key-release administrator, side channels, or physical attack. The platform operator stays trusted for availability — they can still power the box off, block the network, or refuse to launch the VM. Confidential computing isn’t a defense against denial of service.