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DuPage Medical Group

Disclosed Aug 30, 20215 years ago655,384 affectedConfirmed

Official notice

The covered entity (CE), DuPage Medical Group, reported that it was the subject of a cyber-attack that affected the protected health information (PHI) of 655,384 individuals. The PHI involved included names, addresses, dates of birth, Social Security numbers, diagnoses, and other treatment information. The CE notified HHS, the affected individuals, the media, and provided substitute notice. In response to the breach, the CE provided complimentary credit monitoring services and implemented additional administrative, technical, and security safeguards to better protect its PHI.

What is known

People affected655,384 (as reported to HHS)
DisclosedAug 30, 2021
HappenedJul 12, 2021
AttackHacking
Data exposedNames, Health
SectorHealthcare · US
StatusConfirmed

Sources

Notices filed

WhereFiledPeople
Indiana AGresidents of INAug 30, 20215
HHS archivetotalAug 30, 2021655,384
California AGresidents of CASep 1, 2021
History of this record
  • 2026-09-25 · attack: unknown to hacking · backfill source
  • 2026-09-25 · data_types: [] to ["names","health"] · backfill source
  • 2026-09-25 · records_basis: organization to hhs · backfill source
  • 2026-09-25 · records: 655355 to 655384 · backfill source
  • 2026-09-25 · summary: empty to The covered entity (CE), DuPage Medical Group, reported that it was the subject of a cyber-attack that affected the protected health information (PHI) of 655,384 individuals. The PHI involved included names, addresses, dates of birth, Socia · backfill source
  • 2026-09-25 · records_basis: empty to organization · backfill source
  • 2026-09-25 · records: empty to 655355 · backfill source
  • 2026-09-25 · disclosed: 2021-09-01 to 2021-08-30 · backfill source
  • 2026-09-25 · added · backfill source

First seen 2026-09-25 (California AG), confirmed by California AG. Record counts are as reported. Not legal advice.

Everything about DuPage Medical Group

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