Skip to content

Columbia University

Disclosed Aug 7, 20251 year ago3,067,242 affectedConfirmed

Official notice

Hacker steals data of 868,969 Columbia students, applicants and staff

Columbia University told Maine's attorney general that a hacker who breached its network in May 2025, discovered after a June 24 outage, stole data on 868,969 people including names, birth dates, SSNs, contact details, academic history and financial aid and health information.

What is known

People affected3,067,242 (as reported by the organization)
DisclosedAug 7, 2025
DiscoveredJul 8, 2025
HappenedMay 16, 2025
AttackHacking
Data exposedNames, Health, Insurance, Credentials and tokens, Dates of birth, Social Security numbers, Addresses, Phone numbers, Education records, Financial, Other, Government IDs, Payment cards
SectorEducation · US
StatusConfirmed

Sources

Source
California Attorney General breach notice: Columbia Universityoag.ca.gov · Official notice
Washington Attorney General breach notice: Columbia Universityatg.wa.gov · Official notice
Notice letter filed with the Delaware DOJ: Columbia Universityattorneygeneral.delaware.gov · Official notice
Oregon DOJ breach notice: Columbia Universityjustice.oregon.gov · Official notice
Columbia University data breach impacts nearly 870,000 individualsbleepingcomputer.com · News
Texas Attorney General data security breach report BR-0005050: Columbia Universityoag.my.site.com · Official notice
Vermont Attorney General: 2025-08-07 Columbia University Data Breach Notice to Consumersago.vermont.gov · Official notice
Indiana Attorney General 2025 data breach report: Columbia Universityin.gov · Official notice

Notices filed

WhereFiledPeople
California AGresidents of CAAug 7, 2025
Washington AGresidents of WAAug 7, 202554,075
Delaware DOJresidents of DEAug 7, 20251,818
Oregon DOJresidents of ORAug 7, 2025868,969
ResearchtotalAug 7, 2025868,969
Vermont AGresidents of VTAug 7, 2025
Indiana AGresidents of INAug 7, 20254,078
Texas AGresidents of TXMay 20161,544
History of this record
  • 2026-09-25 · source: empty to https://www.in.gov/attorneygeneral/consumer-protection-division/id-theft-prevention/files/DB-Year-to-Date-Report-2025.pdf · backfill source
  • 2026-09-25 · source: empty to https://ago.vermont.gov/document/2025-08-07-columbia-university-data-breach-notice-consumers · backfill source
  • 2026-09-25 · data_types: ["names","health","insurance","credentials","dob","ssn","addresses","phone","education","financial","other"] to ["names","health","insurance","credentials","dob","ssn","addresses","phone","education","financial","other","government-id","payment-card"] · backfill source
  • 2026-09-25 · records: 868969 to 3067242 · backfill source
  • 2026-09-25 · data_types: ["names","health","insurance","credentials"] to ["names","health","insurance","credentials","dob","ssn","addresses","phone","education","financial","other"] · seed source
  • 2026-09-25 · summary: empty to Columbia University told Maine's attorney general that a hacker who breached its network in May 2025, discovered after a June 24 outage, stole data on 868,969 people including names, birth dates, SSNs, contact details, academic history and · seed source
  • 2026-09-25 · title: empty to Hacker steals data of 868,969 Columbia students, applicants and staff · seed source
  • 2026-09-25 · data_types: [] to ["names","health","insurance","credentials"] · backfill source
  • 2026-09-25 · records_basis: empty to organization · backfill source
  • 2026-09-25 · records: empty to 868969 · backfill source
  • 2026-09-25 · attack: unknown to hacking · backfill source
  • 2026-09-25 · discovered: empty to 2025-07-08 · 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 Columbia University

New breaches by email

Wednesdays, only in weeks with newly disclosed breaches, the largest first.

Double opt-in. Unsubscribe any time.