Data Breach Definition

Howard Poston
Jul 27, 2023
Data Breach Definition

What is a Data Breach?

Companies commonly hold large amounts of sensitive and private data. For example, an organization’s customer database may include names, addresses, payment card information, and other sensitive data. An organization also has valuable company data such as intellectual property, marking plans, financial data, and personnel records.

A data breach is an incident in which this sensitive data is leaked or accessed by an unauthorized party. Data breaches can be carried out in various ways and can be intentional or accidental.

How Does a Data Breach Happen?

A data breach is any event that exposes non-public information to unauthorized users. Some common causes of data breaches include:

  • Malware: Several types of malware — such as ransomware and infostealers — have the ability to collect sensitive information from infected systems. These malware variants are designed to exfiltrate this stolen data to an attacker via command and control (C2) infrastructure.
  • Web Application Vulnerabilities: Web application vulnerabilities such as SQL injection or remote code execution (RCE) vulnerabilities could enable an attacker to access and leak sensitive corporate or customer data.
  • Insecure Cloud Storage: Companies are increasingly turning to cloud environments for data storage. However, unfamiliarity with cloud security and the ease of making data public in the cloud — using link-based sharing for example — can result in a data breach.
  • Lost/Stolen Devices: Lost and stolen devices can also be a cause of a data breach. For example, a USB drive left on the metro or a laptop stolen from a car can contain sensitive customer and corporate data.

The Implications of a Data Breach

A data breach is one of the most damaging cybersecurity incidents that an organization can experience. Some common impacts of a data breach include:

  • Financial Losses: Data breaches can be extremely expensive for an organization. According to the 2023 Cost of a Data Breach report, the average cost of a data breach was $4.45 million.
  • Lost Productivity: A data breach is a disruptive event that redirects resources towards remediation and recovery. As a result, an organization may be less efficient after a breach, and resources may be consumed that otherwise would have been used for other purposes.
  • Reputational Damage: A large data breach can cause reputational damage to an organization, especially if it appears to have been the result of negligence. Customers may require compensation, and the organization may lose business as a result.
  • Legal and Regulatory Penalties: Numerous laws and regulations protect customers’ sensitive and personal data. A data breach may result in fines from regulators or class action lawsuits.

Protecting Against Data Breaches

Data breaches are a common fear for organizations due to their potential costs and reputational impacts. Some ways to reduce the risk of a data breach include:

  • Access Control: The use of strong authentication and least-privilege access controls can make data breaches less likely by increasing the difficulty for an attacker to access sensitive data.
  • Encryption: Data encryption is one of the most effective defenses against data breaches. Only someone with access to the secret key can decrypt and use the data.
  • Data Loss Prevention: Data loss prevention (DLP) solutions can identify and block flows of sensitive data from leaving the corporate network.
  • Patch Management: Regular vulnerability scans and rapid patching can help to identify and close vulnerabilities or configuration errors that an attacker could use to access and breach sensitive data.
  • Email and Endpoint Security: Phishing and malware are common causes of data breaches, so solutions to identify and block these attacks can help with managing the data breach threat.


Data breaches are a common fear for organizations. Maintaining data visibility and implementing data security best practices can help an organization to reduce its risk of these incidents.

Howard Poston

Howard Poston is a copywriter, author, and course developer with experience in cybersecurity and blockchain security, cryptography, and malware analysis. He has an MS in Cyber Operations, a decade of experience in cybersecurity, and over five years of experience as a freelance consultant.

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