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Curriculum/Cybersecurity/Data Leakage Prevention/What is Data Leakage?
30 minBeginner

What is Data Leakage?

After this lesson, you will be able to: Understand how and why data leaves organizations.

Data leakage is the unauthorized exit of sensitive data, sometimes through hacks, but often through mistakes: a misconfigured S3 bucket, a forwarded email, a USB stick left on a train. This lesson covers the categories and the human factor.

Why data leakage matters

Most breaches reported in the news involve data leaving an organization, credentials, customer data, IP, source code. The financial and reputational cost is often higher than the cost of intrusion itself.

💡 Three categories of leakage

Malicious, insider exfiltrates data, attacker dumps DB. Accidental, wrong recipient on email, public S3. Negligent, no encryption on backups, lost laptops without disk encryption.

Common leak vectors

  1. 1

    1. Email, sending sensitive data to wrong recipient.

  2. 2

    2. Cloud storage, public buckets, share links.

  3. 3

    3. USB/removable media, physical exfiltration.

  4. 4

    4. Personal devices. BYOD blurring lines.

  5. 5

    5. Third parties, vendors with poor security.

Quick Check

Most common cause of data leakage in 2024 reports?

Take a guess.

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