6.6RAG Security Best Practices
Content sanitization on ingestion. Strip hidden HTML, invisible characters, and known injection patterns before storing documents in the vector store.
Trust levels for documents. Differentiate between trusted (company documentation) and untrusted (user uploads) documents. Apply stricter filtering to untrusted sources.
Citation verification. Implement automated checks that citations reference real documents and that quoted text actually appears in the source.
Context window management. Implement explicit strategies for handling overflow: relevance-based truncation, summarization, and user notification.
Output scanning. Apply the same data leakage scanner to RAG responses as to any other LLM output.
Retrieval monitoring. Log which documents are retrieved and used for each query. Anomalous retrieval patterns (one document appearing in every query) may indicate poisoning.
RAG security is a rapidly evolving field. As RAG architectures become more complex (multi-hop retrieval, agentic RAG), the attack surface grows. Test early, test often, and monitor in production.