Advancing Cyber Incident Timeline Analysis Through Rule Based AI and Large Language Models

Timeline Analysis (TA) is a key part of Timeline Forensics (TF) in Digital Forensics (DF), focusing primarily on examining and analysing temporal digital artefacts such as timestamps, derived from event logs, file metadata, and other related data to correlate events resulting from cyber incidents and reconstruct their chronological timeline. Traditional tools often struggle to efficiently process the vast volume and variety of data acquired during DF investigations and Incident Response (IR) processes. This paper presents a novel framework, GenDFIR, that combines Rule-Based Artificial Intelligence (R-BAI) algorithms with Large Language Models (LLMs) to advance and automate the TA process. Our approach consists of two main stages (1) We use R-BAI to identify and select anomalous digital artefacts based on predefined rules. (2) The selected artefacts are then converted into embeddings for processing by an LLM with the help of a Retrieval-Augmented Generation (RAG) agent. The LLM consequently leverages its capabilities to perform automated TA on the artefacts and predict potential incident scenarios. To validate our framework, we evaluate GenDFIR performance, efficiency, and reliability using various metrics across synthetic cyber incident simulation scenarios. This paper presents a proof of concept, where the findings demonstrate the significant potential of integrating R-BAI and LLMs for TA. This novel approach highlights the power of Generative AI (GenAI), specifically LLMs, and opens new avenues for advanced threat detection and incident reconstruction, representing a significant step forward in the field.