This assessment shows how a small team that runs a hosted large language model can find, rate and control the risks that matter most to its data, access and service. Eight risks were chosen because they are plausible in everyday assistant work. Prompt injection, data leakage through prompts and logs, and compromised access keys carry the highest scores before controls. Each risk is scored before controls and again after existing and added controls. Most risks fall to Medium or Low once the added controls are in place, though prompt injection and key compromise stay at Medium because the impact remains serious. The first actions are a masking filter for prompts, a secrets vault for keys, weekly reply sampling and pinned versions. The team is a teaching example, so every score illustrates the method, not a real organization.
Scope
This assessment covers a hypothetical team that connects a hosted large language model to an internal assistant, a customer-facing chat feature, prompt and response logs, and stored company documents. It looks at confidentiality, integrity and availability of data, access to the model, third-party dependency, privacy duties, logging and incident response. It does not test any real system or provider. Jurisdiction, provider terms and technical architecture are not specified, so they are treated as labeled assumptions.
Context
The team has a product owner, two developers, an IT administrator and a data protection lead. Users type requests into a web interface, which sends them with selected company documents to the hosted model using an application programming interface key. Responses are stored in a log for quality review. Each risk is scored before controls to show its natural level, then again after existing controls and the additional controls that should be added, so students can see how treatment changes the score.
Objectives, assets and stakeholders
The objective is to deliver a useful assistant while protecting confidential data, keeping access limited to authorized people, meeting privacy duties and keeping the service available. The assets in scope are customer and company data sent through prompts, stored logs, the provider account and its keys, the application code and its libraries, and the trust customers place in the replies. Stakeholders include the product owner, developers, the IT administrator, the data protection lead, customers, staff who use the tool, the provider and the relevant regulator. Every risk has one owner role, and the product owner keeps the register current and reports to leadership each quarter.