arXiv subjects

Fengxiu Zhang

Publications and source records attributed to Fengxiu Zhang.

7 recordsLinked to original sources

arXiv2026

Assessing Socio-Cyber Vulnerability Using Survey and Social Media Data

The rapid growth of social media participation has increased exposure to socially engineered cyber threats (e.g., phishing, romance fraud, and tech-support scams), yet prevailing assessment tools remain fragmented: the Common Vulnerability Scoring System (CVSS) is primarily technical and largely omits human susceptibility, while the Social Vulnerability Index (SVI) is community-oriented and lacks cyber-specific modeling. To address this gap, we propose the Social Cyber Vulnerability Index (SCVI), an interpretable, uncertainty-aware metric combining two components: (i) an Individual Vulnerability Index (IVI), capturing awareness, behavior, psychological factors, and prior victimization, and (ii) an Attack Severity Index (ASI), capturing attack frequency, consequences, and sophistication. We validate SCVI across heterogeneous modalities: a nationally scoped survey (iPoll; 4,596 U.S. adults) and social-media narratives (450 Reddit r/scams reports, 2016-2024), demonstrating computation from both structured questionnaires and CI-driven feature extraction from text. Sensitivity analysis and 10,000-iteration Monte Carlo simulations show stable rankings under plausible weight variability and reveal context-dependent drivers. SCVI captures distinct socio-technical signals (Spearman correlation with CVSS $\rho = 0.33$; with SVI $\rho \approx -0.01$) and surfaces demographic and regional disparities. SCVI also provides substantially stronger separation between victim and non-victim groups than CVSS and SVI, supporting identification of high-risk populations and prioritization of interventions against emerging AI-enabled scams.

cs.SI↗

arXiv2025

Scam Shield: Multi-Model Voting and Fine-Tuned LLMs Against Adversarial Attacks

Scam detection remains a critical challenge in cybersecurity as adversaries craft messages that evade automated filters. We propose a Hierarchical Scam Detection System (HSDS) that combines a lightweight multi-model voting front end with a fine-tuned LLaMA 3.1 8B Instruct back end to improve accuracy and robustness against adversarial attacks. An ensemble of four classifiers provides preliminary predictions through majority vote, and ambiguous cases are escalated to the fine-tuned model, which is optimized with adversarial training to reduce misclassification. Experiments show that this hierarchical design both improves adversarial scam detection and shortens inference time by routing most cases away from the LLM, outperforming traditional machine-learning baselines and proprietary LLM baselines. The findings highlight the effectiveness of a hybrid voting mechanism and adversarial fine-tuning in fortifying LLMs against evolving scam tactics, enhancing the resilience of automated scam detection systems.

cs.CR↗

arXiv2025

Situational Preparedness Dynamics for Sequential Tropical Cyclone Hazards

Sequential tropical cyclone hazards--two tropical cyclones (TCs) making landfall in the same region within a short time--are becoming increasingly likely. This study investigates situational preparedness dynamics for six sequential TC events that affected seven states in the United States from 2020 to 2024. We find a combined effect of forecast wind speed and landfall sequence of a TC. Stronger forecast wind is always associated with higher preparedness levels. People tend to show a higher preparedness level for the second TC but are more sensitive to the increasing forecast wind speed of the first TC. We also find that the counties showing high preparedness levels for the first TC consistently show high preparedness levels for the subsequent one. Power outages induced by the first TC significantly increase preparedness for the subsequent TC (e.g., approximately 13% pct for mobility needs preparedness and 24% for structural reinforcement preparedness when increasing one-unit customers out). We identified spatial dependency in preparedness across counties. Power outage experiences in first TCs show statistically significant spillover effects on neighboring counties' preparedness levels for second TCs. Throughout sequential TCs, people with access and functional needs consistently show lower preparedness levels.

physics.soc-ph↗

arXiv2025

SCVI: Bridging Social and Cyber Dimensions for Comprehensive Vulnerability Assessment

The rise of cyber threats on social media platforms necessitates advanced metrics to assess and mitigate social cyber vulnerabilities. This paper presents the Social Cyber Vulnerability Index (SCVI), a novel framework integrating individual-level factors (e.g., awareness, behavioral traits, psychological attributes) and attack-level characteristics (e.g., frequency, consequence, sophistication) for comprehensive socio-cyber vulnerability assessment. SCVI is validated using survey data (iPoll) and textual data (Reddit scam reports), demonstrating adaptability across modalities while revealing demographic disparities and regional vulnerabilities. Comparative analyses with the Common Vulnerability Scoring System (CVSS) and the Social Vulnerability Index (SVI) show the superior ability of SCVI to capture nuanced socio-technical risks. Monte Carlo-based weight variability analysis confirms SCVI is robust and highlights its utility in identifying high-risk groups. By addressing gaps in traditional metrics, SCVI offers actionable insights for policymakers and practitioners, advancing inclusive strategies to mitigate emerging threats such as AI-powered phishing and deepfake scams.

cs.CR↗

arXiv2025

Uncovering cooling center usage as an adaptation strategy for hurricane-blackout-heat compound hazards during Hurricane Beryl (2024)

Extreme heat and hurricane-induced blackouts could occur simultaneously in the summer, posing great challenges to community health and well-being. Cooling centers serve as a key adaptation strategy to alleviate heat stress, especially among heat-vulnerable populations. This study leverages mobility data to examine how affected communities utilize cooling centers in response to hurricane-blackout-heat compound hazards. Additionally, it examines disparities in cooling center usage, focusing on individuals with access and functional needs (AFNs) who are usually overlooked in emergency management practices. These populations include but are limited to older adults, individuals with limited English proficiency, people with disabilities, those without vehicle access, and lower-income households. Using the empirical case of Hurricane Beryl (2024) in Harris County, Texas, we find no statistically significant difference in visiting formal (established by the government) and informal cooling centers (operated by volunteer organizations). Census block groups closer to the nearest cooling center and those with lower income are more likely to seek shelter from extreme heat at cooling centers in the aftermath of Hurricane Beryl. Lower-income block groups also tend to be situated closer to cooling centers, suggesting that Harris County may have strategically placed them in areas with greater social vulnerability. Furthermore, we investigate visiting hotels as an alternative but more expensive adaptation strategy during Hurricane Beryl. Between these two adaptation options, shorter distances to cooling centers, lower income, and elder age are statistically significantly associated with a higher probability of visiting cooling centers rather than hotels, while limited English proficiency significantly decreases such probability.

physics.soc-ph↗

arXiv2024

Exposing LLM Vulnerabilities: Adversarial Scam Detection and Performance

Can we trust Large Language Models (LLMs) to accurately predict scam? This paper investigates the vulnerabilities of LLMs when facing adversarial scam messages for the task of scam detection. We addressed this issue by creating a comprehensive dataset with fine-grained labels of scam messages, including both original and adversarial scam messages. The dataset extended traditional binary classes for the scam detection task into more nuanced scam types. Our analysis showed how adversarial examples took advantage of vulnerabilities of a LLM, leading to high misclassification rate. We evaluated the performance of LLMs on these adversarial scam messages and proposed strategies to improve their robustness.

cs.CR↗

arXiv2022

Automated Integration of Infrastructure Component Status for Real-Time Restoration Progress Control: Case Study of Highway System in Hurricane Harvey

Following extreme events, efficient restoration of infrastructure systems is critical to sustaining community lifelines. During the process, effective monitoring and control of the infrastructure restoration progress is critical. This research proposes a systematic approach that automatically integrates component-level restoration status to achieve real-time forecasting of overall infrastructure restoration progress. In this research, the approach is mainly designed for transportation infrastructure restoration following Hurricane Harvey. In detail, the component-level restoration status is linked to the restoration progress forecasting through network modeling and earned value method. Once the new component restoration status is collected, the information is automatically integrated to update the overall restoration progress forecasting. Academically, an approach is proposed to automatically transform the component-level restoration information to overall restoration progress. In practice, the approach expects to ease the communication and coordination efforts between emergency managers, thereby facilitating timely identification and resolution of issues for rapid infrastructure restoration.

cs.CE↗