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Insider Threat Matrix™Insider Threat Matrix™
  • ID: IF022.002
  • Created: 22nd April 2025
  • Updated: 22nd October 2025
  • Platforms: WindowsLinuxMacOSiOSAndroid
  • Contributor: Ryan Bellows

PII Leakage (Personally Identifiable Information)

PII (Personally Identifiable Information) leakage refers to the unauthorized disclosure, exposure, or mishandling of information that can be used to identify an individual, such as names, addresses, phone numbers, national identification numbers, financial data, or biometric records. In the context of insider threat, PII leakage may occur through negligence, misconfiguration, policy violations, or malicious intent.

 

Insiders may leak PII by sending unencrypted spreadsheets via email, exporting user records from customer databases, misusing access to HR systems, or storing sensitive personal data in unsecured locations (e.g., shared drives or cloud storage without proper access controls). In some cases, PII may be leaked unintentionally through logs, collaboration platforms, or default settings that fail to mask sensitive fields.

 

The consequences of PII leakage can be severe—impacting individuals through identity theft or financial fraud, and exposing organizations to legal penalties, reputational harm, and regulatory sanctions under frameworks such as GDPR, CCPA, or HIPAA.

 

Examples of Infringement:

  • An employee downloads and shares a list of customer contact details without authorization.
  • PII is inadvertently exposed in error logs or email footers shared externally.
  • HR data containing employee National Insurance or Social Security numbers is copied to a personal cloud storage account.