RAG-Driven Cybersecurity Intelligence: Leveraging Semantic Search for Improved Threat Detection

Retrieval-Augmented Generation (RAG) unifies dense retrieval with generative models to ground generated outputs in external documents, suppressing hallucinations and supporting up-to-date, domain-specific reasoning. We introduce an architecture combining semantic search (dense vector retrieval and knowledge-graph indexing) with RAG workflows to improve CTI ingestion, correlation and detection. The system ingests heterogeneous CTI sources (OSINT reports, vendor feeds, malware descriptions) and locks and loads the semantic chunking and entity linking process that indexes embeddings in a vector store alongside a cybersecurity knowledge graph for relational reasoning. A policy-aware RAGenerator which produces ranked threat hypotheses and suggested actions. Methodologically, we deploy as prototype a dense bi-encoder retriever and FAISS index alongside an off-the-shelf seq2seq generator fine-tuned on CTI summarization tasks and a knowledge graph with Neo4j underneath. The evaluation is based on a set of 2,400 CTI incident reports and synthetic network alert sequences with known ground truth; metrics include detection precision, recall, F1 measure, time- to-context (TTC), and reduction in analyst workload. On the other hand, results demonstrate a 25.7% increase in detection F1 over keyword/TTP-matching based baseline and an average decrease of 31% in analyst triage time for RAG-driven pipeline, while knowledge-graph augmentation enhanced true positive correlation of multi-stage attacks by 22%. It also lowered hallucination rate on generated advisories by 45% (as measured with ground-truth grounding). Conclusion: Only indexing corpus quality reliance and possible privacy leakage in retrieval. In the future, secure retrieval technique and automated counter-adversarial training will be perfected.