Substack data breach exposed user email addresses and phone numbers for months before CEO Chris Best confirmed the October ...

Substack says hackers accessed user emails, phone numbers, and internal metadata in October 2025, with a database of 697,313 records later posted online.

Substack won't share official numbers, but it seems like a pretty significant data breach.

Substack said that customer data was accessed in October 2025, but wasn't discovered until early February.

Substack has removed several publications for inciting violence, the newsletter publisher said in a statement shared with CNN Tuesday, as writers from across the platform threaten ed to quit over the ...

According to The Guardian, several newsletters promoting Nazi ideology and antisemitic conspiracy theories were operating on ...

The hacker claims to have stolen nearly 700,000 Substack user records, including email addresses and phone numbers.

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