Substack security incident history
Hacking, data breaches and other security incidents involving Substack, with related coverage.
Incidents: 1 · Most recent
Substack user data leaked via exploited API flaw
662.8KImpact: 662,752 user records
An attack exploiting an API flaw at Substack leaked user email addresses, phone numbers and other information. 662,752 user records were published on a cybercrime forum, and Substack notified users of the breach. The incident was discovered about four months after it occurred.
Related reports: 11 · last report →