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Slack

Disclosed Mar 27, 201511 years agoUnverified

Slack's central user database breached, exposing usernames and password hashes

Slack announced in a blog post that attackers had accessed its user database of usernames, emails and hashed passwords, and it rolled out two-factor authentication in response.

What is known

People affectedNot stated in the sources we have
DisclosedMar 27, 2015
AttackHacking
Data exposedCredentials and tokens, Emails, Passwords
SectorTech · US
StatusUnverified: not yet confirmed by an official notice, a filing or the organization

Sources

Notices filed

WhereFiledPeople
ResearchtotalMar 27, 2015
History of this record
  • 2026-09-25 · added · seed source

First seen 2026-09-25 (Research). Record counts are as reported. Not legal advice.

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