Substack
ModerateConfirmedDigital services
In October 2025, Substack suffered a data breach. 663,121 accounts were affected. The exposed data includes email addresses and phone numbers.
- Disclosed on
- February 6, 2026
- Incident dated
- October 23, 2025
- Accounts affected
- 663,121
- Sector
- Digital services
- Country
- International or undetermined
- Cause
- Undisclosed
Exposed data
- Email address
- Phone number
You are only affected if you had an account or an order with this organisation.
What you can do
- Expect phishing attempts quoting your name and this company. A message that knows your details is not legitimate for that reason.
- You can ask the organisation exactly what was exposed about you (right of access), and complain to the DPA if no answer comes within a month.
Sources
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