Every public data breach

Disclosed this week44On record26,355

44 disclosed this week · 26,355 on record

Sierra Club

Disclosed Oct 4, 2023813 affectedConfirmed

Official notice

What is known

People affected813 (as reported by the organization)
DisclosedOct 4, 2023
HappenedFeb 3, 2023
AttackNot stated
Data exposedNot stated
SectorNonprofit · US
StatusConfirmed

Sources

Official noticeago.vermont.gov
Vermont Attorney General: 2023-10-05 Sierra Club Data Breach Notice to Consumers
Official noticein.gov
Indiana Attorney General 2023 data breach report: Sierra Club

Notices filed

Residents of INOct 4, 2023
Indiana AG8 people
Residents of VTOct 5, 2023
Vermont AGCount not stated
History of this record
records_basis2026-09-25
empty to organizationby backfillSource
records2026-09-25
empty to 813by backfillSource
disclosed2026-09-25
2023-10-05 to 2023-10-04by backfillSource
occurred2026-09-25
empty to 2023-02-03by backfillSource
Added2026-09-25
First recordedby backfillSource

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

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