Do firms underreport information on cyber-attacks? Evidence from capital markets

• 成果类型: Article
• 署名作者: Amir, Eli; Levi, Shai; Livne, Tsafrir
• 署名单位: Tel Aviv University; University of North Carolina; University of North Carolina Chapel Hill
• 刊物名称: REVIEW OF ACCOUNTING STUDIES
• ISSN/ISSBN: 1380-6653
• DOI: 10.1007/s11142-018-9452-4
• 发表日期: 2018
• 页码: 1177-1206
• 关键词: security breach announcements; disclosure; IMPACT; delay

摘要

Firms should disclose information on material cyber-attacks. However, because managers have incentives to withhold negative information, and investors cannot discover most cyber-attacks independently, firms may underreport them. Using data on cyber-attacks that firms voluntarily disclosed, and those that were withheld and later discovered by sources outside the firm, we estimate the extent to which firms withhold information on cyber-attacks. We find withheld cyber-attacks are associated with a decline of approximately 3.6% in equity values in the month the attack is discovered, and disclosed attacks with a substantially lower decline of 0.7%. The evidence is consistent with managers not disclosing negative information below a certain threshold and withholding information on the more severe attacks. Using the market reactions to withheld and disclosed attacks, we estimate that managers disclose information on cyber-attacks when investors already suspect a high likelihood (40%) of an attack.