An information security event is a specific event that may have an impact on a system, service or network and indicates a possible violation of information security policies, a failure of safeguards or a previously unknown situation that could pose a security risk.
An information security incident is a single incident or a series of unwanted or unexpected security-related incidents that are considered most likely to compromise business operations or information security. In this context, “information security” refers to the protection of confidentiality and integrity as well as the availability of information.