Market Reactions To Cybersecurity Incidents: A Case Study Approach

This paper examines the impact of cybersecurity breaches on the stock prices of publicly traded companies, focusing on notable incidents involving Capital One, Equifax, Facebook, Google, JBS S.A., MGM Resorts International, Nvidia, Okta, SolarWinds, and T-Mobile. Employing event study methodology, we analyze stock price changes relative to the Dow Jones Industrial Average (DJIA) across various time windows surrounding the breach disclosures. Our statistical analysis includes paired t-tests, Wilcoxon signed-rank tests, and correlation analyses to determine the significance and nature of these impacts. Results consistently show statistically significant deviations in stock prices following breach announcements, underscoring the profound financial repercussions. The findings highlight the necessity for robust cybersecurity measures and proactive incident response strategies to mitigate the adverse effects on market performance. This comprehensive study contributes to the understanding of cybersecurity risks and their implications for investor confidence and corporate financial stability, offering valuable insights for stakeholders in managing and responding to cyber threats.