Maximus

Disclosed Jun 18, 20215 years ago334,690 affectedConfirmed

Official notice

What is known

People affected	334,690 (as reported by the organization)
Disclosed	Jun 18, 2021
Discovered	May 19, 2021
Happened	May 17, 2021
Attack	Hacking
Data exposed	Not stated
Sector	Government · US
Status	Confirmed

Sources

Source	Kind
California Attorney General breach notice: Maximusoag.ca.gov · Official notice	Official notice
Washington Attorney General breach notice: Maximusatg.wa.gov · Official notice	Official notice
Oregon DOJ breach notice: Maximusjustice.oregon.gov · Official notice	Official notice
Indiana Attorney General 2021 data breach report: Maximusin.gov · Official notice	Official notice

Notices filed

Where	Filed	People
Washington AGresidents of WA	Jun 18, 2021	2,560
Indiana AGresidents of IN	Jun 18, 2021	6,458
California AGresidents of CA	Jun 23, 2021
Oregon DOJresidents of OR	Jun 23, 2021	334,690

Other breaches at Maximus

Breach	Disclosed	Attack	Sector	Status	Affected
Disclosed Apr 25, 2025Apr 25, 20251 year agoInsider	Apr 25, 20251 year ago	Insider	Healthcare	Confirmed	4,955
MOVEit breach exposes personal and health data of 8 to 11 million peopleJul 26, 20233 years agoSupply chain	Jul 26, 20233 years ago	Supply chain	Government	Confirmed	9.2M

History of this record

2026-09-25 · sector: other to government · backfill source
2026-09-25 · records_basis: empty to organization · backfill source
2026-09-25 · records: empty to 334690 · backfill source
2026-09-25 · attack: unknown to hacking · backfill source
2026-09-25 · disclosed: 2021-06-23 to 2021-06-18 · backfill source
2026-09-25 · discovered: empty to 2021-05-19 · 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.

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