Cyber threat intelligence on past attacks may help with attack reconstruction and the prediction of the course of an ongoing attack by providing deeper understanding of the tools and attack patterns used by attackers. Therefore, cyber security analysts employ threat intelligence, alert correlations, machine learning, and advanced visualizations in order to produce sound attack hypotheses. In this paper, we present AttackDB, a multi-level threat knowledge base that combines data from multiple threat intelligence sources to associate high-level ATT&CK techniques with low-level telemetry found in behavioral malware reports. We also present the Attack Hypothesis Generator which relies on knowledge graph traversal algorithms and a variety of link prediction methods to automatically infer ATT&CK techniques from a set of observable artifacts. Results of experiments performed with 53K VirusTotal reports indicate that the proposed algorithms employed by the Attack Hypothesis Generator are able to produce accurate adversarial technique hypotheses with a mean average precision greater than 0.5 and area under the receiver operating characteristic curve of over 0.8 when it is implemented on the basis of AttackDB. The presented toolkit will help analysts to improve the accuracy of attack hypotheses and to automate the attack hypothesis generation process.

Analysts in Security Operations Centers (SOCs) are often occupied with time-consuming investigations of alerts from Network Intrusion Detection Systems (NIDSs). Many NIDS rules lack clear explanations and associations with attack techniques, complicating the alert triage and the generation of attack hypotheses. Large Language Models (LLMs) may be a promising technology to reduce the alert explainability gap by associating rules with attack techniques. In this paper, we investigate the ability of three prominent LLMs (ChatGPT, Claude, and Gemini) to reason about NIDS rules while labeling them with MITRE ATT&CK tactics and techniques. We discuss prompt design and present experiments performed with 973 Snort rules. Our results indicate that while LLMs provide explainable, scalable, and efficient initial mappings, traditional machine learning (ML) models consistently outperform them in accuracy, achieving higher precision, recall, and F1-scores. These results highlight the potential for hybrid LLM-ML approaches to enhance SOC operations and better address the evolving threat landscape. By utilizing automation, the presented methods will enhance the analysis efficiency of SOC alerts, and decrease workloads for analysts.

Analysts in Security Operations Centers (SOCs) are often occupied with time-consuming investigations of alerts from Network Intrusion Detection Systems (NIDS). Many NIDS rules lack clear explanations and associations with attack techniques, complicating the alert triage and the generation of attack hypotheses. Large Language Models (LLMs) may be a promising technology to reduce the alert explainability gap by associating rules with attack techniques. In this paper, we investigate the ability of three prominent LLMs (ChatGPT, Claude, and Gemini) to reason about NIDS rules while labeling them with MITRE ATT&CK tactics and techniques. We discuss prompt design and present experiments performed with 973 Snort rules. Our results indicate that while LLMs provide explainable, scalable, and efficient initial mappings, traditional Machine Learning (ML) models consistently outperform them in accuracy, achieving higher precision, recall, and F1-scores. These results highlight the potential for hybrid LLM-ML approaches to enhance SOC operations and better address the evolving threat landscape.