Support chatbot for an online store
A retailer in Oradea wants an assistant that sees the signed-in customer's orders but no one else's, and cannot be talked into granting discounts.
LLM application security covers the risks a firewall cannot see: instructions hidden in content, answers used without checking, documents shown to someone with no right to read them, and agents holding too many permissions. We test and harden chatbots and RAG applications hosted with us, with prompts, indexes and logs kept in the EU.
Of the OWASP Top 10 for LLM applications, four come back on nearly every project. Prompt injection: instructions hidden in a document, e-mail or page that the assistant reads and then obeys. Unsafe output handling: the model's answer lands directly in HTML, a shell or a query. Sensitive data leakage: one user's context shows up in another's answer or in the logs. Excessive agency: the agent holds keys and rights for actions it should not take alone.
The surface is new but the economics of attack are familiar: cheap to try, automated and repeatable. An attacker plants instructions in a page you will index, then asks the assistant to summarise it and send the content elsewhere, or generates thousands of phrasings until one slips past a filter. Defence cannot be a single system prompt. We layer it: instructions separated from data, guardrails on input and output, PII redaction, access control evaluated at query time, prompt logging and automated red teaming with promptfoo and garak, run as a test on every release.
In a RAG application the index becomes a copy of your documents, and the access filter has to be evaluated on every query, not when the document was indexed. We tie each fragment to its source and to the rights on that source, filter on metadata before generation and check the answer against the fragments the user was actually allowed to see. Documents, embeddings and the index stay on your infrastructure in Frankfurt; if you want no calls to outside providers, we run the embedding model on a GPU server. Citations in the answer make verification possible.
Since 2 August 2026 the EU AI Act places new obligations on organisations that use AI systems; the most visible is transparency, because people must know when they are talking to an automated system. We document the model, the data entering the context, prompt retention, log access and active filters, on top of the GDPR basics: an Article 28 agreement, standard contractual clauses and PII redaction. Assessments are requested from the client panel and use your included hours; a larger red-teaming programme is billed separately, and hours do not carry over.
Every plan includes monthly hours of DevOps, CyberSecurity and Programming work delivered by the 4hosting team: 1 h from cPanel Advanced upwards, 1–8 h on VPS, 5–10 h on dedicated servers depending on the plan, and 10 h on GPU servers. You request them from the client panel, unused hours are not carried into the next month, and extra hours are accepted and billed separately.
Request the assessment in DevOps Services: tell us which model you use, what data enters the context and who uses the application.
We map the flows: indexed sources, tools called by the agent, permissions and logs. We agree the test scenarios and the date you propose.
We run automated and manual red teaming, then implement guardrails, PII redaction, access filters on RAG and rate limits.
You receive the report, the test suite that runs on every release and the documentation for transparency and for your GDPR file.
A retailer in Oradea wants an assistant that sees the signed-in customer's orders but no one else's, and cannot be talked into granting discounts.
A consultancy in Bucharest indexes contracts and notes; the access filter must follow exactly the rights set in its file system.
A medical group wants answers drawn from internal protocols, with patient data redacted before it reaches the model's context.
Instructions slipped into data the model reads: a web page, a PDF, an e-mail, a fragment of the index. A model does not separate your instruction from text asking for something else, so it may follow both. Defence combines role separation, filters and minimal permissions for every tool.
Three main ones: leakage of data placed in the context, false answers presented with confidence, and actions taken by an agent that holds too many rights. Add uncontrolled cost when there are no per-user limits, and transparency duties towards the people who use the chatbot.
The public list of risks specific to language-model applications: prompt injection, unsafe output handling, sensitive data leakage, excessive agency, data poisoning and others. We use it as the checklist for the assessment and as the structure of the report.
Filter access at query time, not at indexing: each fragment carries the rights of its source, and the answer is built only from what the current user may see. Add PII redaction, prompt logging with a short retention period and keep the index on servers in the EU.
Since 2 August 2026 new obligations apply to organisations that use AI systems, the most visible being transparency: people must be told when they interact with an automated system. Document the model, the data in context and prompt retention. We deliver the technical part of that file.
Data you are not allowed to send outside the EU, access secrets, and full personnel or patient files. If the information is needed, redact it first, replace it with identifiers and keep the model on your own infrastructure rather than on a public service.
Request the assessment from the client panel: red teaming on real scenarios, guardrails, RAG access control and transparency documentation.