Newsletter Subscribers Information Exposed
Substack, a popular newsletter platform, has informed users of a data breach that occurred in October 2025, resulting in the unauthorized access of email addresses and phone numbers. The company discovered the breach in February 2026 and has since addressed the security flaw.
Who is at risk
Substack users who provided their email addresses and phone numbers are most at risk.
What to watch for
Be cautious of unexpected emails or text messages requesting personal information or containing suspicious links.
What to do
Remain vigilant against potential phishing attempts and avoid sharing sensitive information through unverified communications.