What is data breach? - Security Term

A data breach is an incident in which sensitive, protected or confidential data has potentially been viewed, stolen or used by an individual unauthorized to do so. Data breaches may involve personal health information (PHI), personally identifiable information (PII), trade secrets or intellectual property.
The most common concept of a data breach is an attacker hacking into a corporate network to steal sensitive data. However, not all data breaches are so dramatic. If an unauthorized hospital employee views a patient's health information on a computer screen over the shoulder of an authorized employee, that also constitutes a data breach.

A number of industry guidelines and government compliance regulations mandate strict governance of sensitive or personal data to avoid data breaches. Within a corporate environment, for example, the Payment Card Industry Data Security Standard (PCI DSS) dictates who may handle and use sensitive PII such as credit card numbers, PINs and bank account numbers in conjunction with names and addresses. Within a healthcare environment, the Health Insurance Portability and Accountability Act (HIPAA) regulates who may see and use PHI such as name, date of birth, Social Security number and health history information.

If anyone who is not specifically authorized to do so views such information, the corporation or healthcare organization charged with protecting that information is said to have suffered a data breach. If a data breach results in identity theft and/or a violation of government or industry compliance mandates, the offending organization may face fines or other civil or criminal prosecution.

source: searchsecurity.techtarget