Publication

Abstract : This paper investigates the impact of cybersecurity incidents on firm value and the complex moderating role of social media discourse. Drawing on publicly disclosed breach data from 2005–2025 and integrating event study methodology with large-scale Twitter and Reddit analytics, the analysis shows that cybersecurity incidents consistently generate negative market responses that deepen over extended time windows, reflecting the gradual resolution of investor uncertainty and anxiety. These reactions are driven primarily by the occurrence of a breach itself rather than by specific attack vectors, suggesting that investors initially interpret breaches as generalized signals of organizational vulnerability, even as recovery trajectories diverge across incident types and organizational contexts. Social media attention further conditions these dynamics: heightened discussion amplifies short-term negative reactions by increasing salience and scrutiny, while sustained, high levels of engagement are associated with improved longer-term recovery, consistent with transparency and information-dissemination effects. By conceptualizing cybersecurity incidents as socio-technical information events, this study advances understanding of how information processing, investor learning, and digital communication jointly shape financial outcomes, offering practical insights for managers, regulators, and policymakers on managing disclosure, communication, and resilience following cybersecurity incidents.