2025
Autores
Palma, A; Antunes, M; Bernardino, J; Alves, A;
Publicação
FUTURE INTERNET
Abstract
The Internet of Vehicles (IoV) presents complex cybersecurity challenges, particularly against Denial-of-Service (DoS) and spoofing attacks targeting the Controller Area Network (CAN) bus. This study leverages the CICIoV2024 dataset, comprising six distinct classes of benign traffic and various types of attacks, to evaluate advanced machine learning techniques for instrusion detection systems (IDS). The models XGBoost, Random Forest, AdaBoost, Extra Trees, Logistic Regression, and Deep Neural Network were tested under realistic, imbalanced data conditions, ensuring that the evaluation reflects real-world scenarios where benign traffic dominates. Using hyperparameter optimization with Optuna, we achieved significant improvements in detection accuracy and robustness. Ensemble methods such as XGBoost and Random Forest consistently demonstrated superior performance, achieving perfect accuracy and macro-average F1-scores, even when detecting minority attack classes, in contrast to previous results for the CICIoV2024 dataset. The integration of optimized hyperparameter tuning and a broader methodological scope culminated in an IDS framework capable of addressing diverse attack scenarios with exceptional precision.
2025
Autores
Fernandes, P; Ciardhuáin, SO; Antunes, M;
Publicação
COMPUTERS & SECURITY
Abstract
Detecting malware in computer networks and data streams from Android devices remains a critical challenge for cybersecurity researchers. While machine learning and deep learning techniques have shown promising results, these approaches often require large volumes of labelled data, offer limited interpretability, and struggle to adapt to sophisticated threats such as zero-day attacks. Moreover, their high computational requirements restrict their applicability in resource-constrained environments. This research proposes an innovative approach that advances the state of the art by offering practical solutions for dynamic and data-limited security scenarios. By integrating natural statistical laws, particularly Benford's law, with dissimilarity functions, a lightweight, fast, and scalable model is developed that eliminates the need for extensive training and large labelled datasets while improving resilience to data imbalance and scalability for large-scale cybersecurity applications. Although Benford's law has demonstrated potential in anomaly detection, its effectiveness is limited by the difficulty of selecting relevant features. To overcome this, the study combines Benford's law with several distance functions, including Median Absolute Deviation, Kullback-Leibler divergence, Euclidean distance, and Pearson correlation, enabling statistically grounded feature selection. Additional metrics, such as the Kolmogorov test, Jensen-Shannon divergence, and Z statistics, were used for model validation. This approach quantifies discrepancies between expected and observed distributions, addressing classic feature selection challenges like redundancy and imbalance. Validated on both balanced and unbalanced datasets, the model achieved strong results: 88.30% accuracy and 85.08% F1-score in the balanced set, 92.75% accuracy and 95.29% F1-score in the unbalanced set. The integration of Benford's law with distance functions significantly reduced false positives and negatives. Compared to traditional Machine Learning methods, which typically require extensive training and large datasets to achieve F1 scores between 92% and 99%, the proposed approach delivers competitive performance while enhancing computational efficiency, robustness, and interpretability. This balance makes it a practical and scalable alternative for real-time or resource-constrained cybersecurity environments.
2025
Autores
Pedroso, DF; Almeida, L; Pulcinelli, LEG; Aisawa, WAA; Dutra, I; Bruschi, SM;
Publicação
IEEE ACCESS
Abstract
Cloud computing technologies offer significant advantages in scalability and performance, enabling rapid deployment of applications. The adoption of microservices-oriented architectures has introduced an ecosystem characterized by an increased number of applications, frameworks, abstraction layers, orchestrators, and hypervisors, all operating within distributed systems. This complexity results in the generation of vast quantities of logs from diverse sources, making the analysis of these events an inherently challenging task, particularly in the absence of automation. To address this issue, Machine Learning techniques leveraging Large Language Models (LLMs) offer a promising approach for dynamically identifying patterns within these events. In this study, we propose a novel anomaly detection framework utilizing a microservices architecture deployed on Kubernetes and Istio, enhanced by an LLM model. The model was trained on various error scenarios, with Chaos Mesh employed as an error injection tool to simulate faults of different natures, and Locust used as a load generator to create workload stress conditions. After an anomaly is detected by the LLM model, we employ a dynamic Bayesian network to provide probabilistic inferences about the incident, proving the relationships between components and assessing the degree of impact among them. Additionally, a ChatBot powered by the same LLM model allows users to interact with the AI, ask questions about the detected incident, and gain deeper insights. The experimental results demonstrated the model's effectiveness, reliably identifying all error events across various test scenarios. While it successfully avoided missing any anomalies, it did produce some false positives, which remain within acceptable limits.
2025
Autores
Freitas, T; Novo, C; Dutra, I; Soares, J; Correia, ME; Shariati, B; Martins, R;
Publicação
SOFTWARE-PRACTICE & EXPERIENCE
Abstract
Background Intrusion Tolerant Systems (ITS) aim to maintain system security despite adversarial presence by limiting the impact of successful attacks. Current ITS risk managers rely heavily on public databases like NVD and Exploit DB, which suffer from long delays in vulnerability evaluation, reducing system responsiveness.Objective This work extends the HAL 9000 Risk Manager to integrate additional real-time threat intelligence sources and employ machine learning techniques to automatically predict and reassess vulnerability risk scores, addressing limitations of existing solutions.Methods A custom-built scraper collects diverse cybersecurity data from multiple Open Source Intelligence (OSINT) platforms, such as NVD, CVE, AlienVault OTX, and OSV. HAL 9000 uses machine learning models for CVE score prediction, vulnerability clustering through scalable algorithms, and reassessment incorporating exploit likelihood and patch availability to dynamically evaluate system configurations.Results Integration of newly scraped data significantly enhances the risk management capabilities, enabling faster detection and mitigation of emerging vulnerabilities with improved resilience and security. Experiments show HAL 9000 provides lower risk and more resilient configurations compared to prior methods while maintaining scalability and automation.Conclusions The proposed enhancements position HAL 9000 as a next-generation autonomous Risk Manager capable of effectively incorporating diverse intelligence sources and machine learning to improve ITS security posture in dynamic threat environments. Future work includes expanding data sources, addressing misinformation risks, and real-world deployments.
2025
Autores
Freitas, T; Silva, E; Yasmin, R; Shoker, A; Correia, ME; Martins, R; Esteves Veríssimo, PJ;
Publicação
101st IEEE Vehicular Technology Conference, VTC Spring 2025, Oslo, Norway, June 17-20, 2025
Abstract
Vehicle cybersecurity has emerged as a critical concern, driven by innovation in the automotive industry, e.g., autonomous, electric, or connected vehicles. Current efforts to address these challenges are constrained by the limited computational resources of vehicles and the reliance on connected infrastructures. This motivated the foundation of Vehicle Security Operations Centers (VSOCs) that extend IT-based Security Operations Centers (SOCs) to cover the entire automotive ecosystem, both the in-vehicle and off-vehicle scopes. Security Orchestration, Automation, and Response (SOAR) tools are considered key for implementing an effective cybersecurity solution. However, existing state-of-the-art solutions depend on infrastructure networks such as 4G, 5G, and WiFi, which often face scalability and congestion issues. To address these limitations, we propose a novel SOAR architecture EVSOAR that leverages the EV charging stations for connectivity and computing to enhance vehicle cybersecurity. Our EV-specific SOAR architecture enables real-time analysis and automated responses to cybersecurity threats closer to the EV, reducing cellular latency, bandwidth, and interference limitations. Our experimental results demonstrate a significant improvement in latency, stability, and scalability through the infrastructure and the capacity to deploy computationally intensive applications that are otherwise infeasible within the resource constraints of individual vehicles.
2025
Autores
Daniel, P; Silva, VF; Ribeiro, P;
Publicação
COMPLEX NETWORKS & THEIR APPLICATIONS XIII, COMPLEX NETWORKS 2024, VOL 1
Abstract
With the huge amount of data that has been collected over time, many methods are being developed to allow better understanding and forecasting in several domains. Time series analysis is a powerful tool to achieve this goal. Despite being a well-established area, there are some gaps, and new methods are emerging to overcome these limitations, such as visibility graphs. Visibility graphs allow the analyses of times series as complex networks and make possible the use of more advanced techniques from another well-established area, network science. In this paper, we present two new efficient approaches for computing natural visibility graphs from times series, one for online scenarios in.O(n log n) and the other for offline scenarios in.O(nm), the latter taking advantage of the number of different values in the time series (m).
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