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This content will become publicly available on October 6, 2026

Title: PA-JJAMA: An LLM Based Intrusion Detection System for CAN Bus Networks
Recent studies have demonstrated significant success in detecting attacks on the Controller Area Network (CAN) bus network using machine learning and deep learning models, including convolutional neural networks and transformer-based architectures. Building on this foundation, our work investigates the use of large language models (LLMs) not only for intrusion detection but also for providing interpretable explanations of their decisions. We fine-tuned three LLMs, i.e., SecureBERT, LLaMA-2, and LLaMA-3, for intrusion detection on CAN bus data. Among them, LLaMA-3 delivered the best results, achieving SOTA performance on the Car-Hacking dataset. Beyond attack classification, we evaluated LLaMA-3’s ability to generate reasoning for its decisions through zero-shot prompting. The model successfully articulated its rationale, particularly for Denial-of- Service (DoS) attacks, demonstrating strong potential for explainability in intrusion detection systems. These findings highlight the potential of LLMs to serve as a highly accurate intrusion detection system while simultaneously providing interpretable explanations, thereby enhancing the investigative capabilities of cybersecurity professionals.  more » « less
Award ID(s):
2146280
PAR ID:
10651645
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
IEEE
Date Published:
Page Range / eLocation ID:
682 to 687
Subject(s) / Keyword(s):
CAN Bus Network, Intrusion Detection System, Large Language Models
Format(s):
Medium: X
Location:
Chicago, IL, USA
Sponsoring Org:
National Science Foundation
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