All Breaches
December 14, 2015 Verified Technology

QuinStreet Data Breach

The major data breach that occurred on the QuinStreet platform in December 2015 caused the personal data of millions of users to fall into unauthorized hands.

4.9 Million
Reported Records
6
Data Types
Critical
Severity
Yes
Verification

Exposed Data Types

6
Dates of birth
Email addresses
IP addresses
Passwords
Usernames
Website activity

Additional Information

Added DateDecember 17, 2016
Breach DateDecember 14, 2015
Domainquinstreet.com
SourceThird party breach
Last Content UpdateJuly 19, 2026

Verification and editorial method

LeakData compares the incident name, date, affected-record count, and exposed data types with accessible sources. Unverified fields are not presented as facts, and records are updated when new evidence becomes available.

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Company Information

Company NameQuinStreet
SectorTechnology
CountryUnited States
Websitequinstreet.com

Risk Level

Critical

The reported impact exceeds 1 million and falls within the critical severity band.

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