Troy Hunt's Mailchimp List data breach

What happened

In March 2025, a phishing attack successfully gained access to Troy Hunt's Mailchimp account and automatically exported a list of people who had subscribed to the newsletter for his personal blog. The exported list contained 16k email addresses and other data automatically collected by Mailchimp including IP address and a derived latitude, longitude and time zone.

What data leaked

• Email addresses
• Geographic locations
• IP addresses
• Latitude and longitude pairs

What to do if you had an account

1. Turn on two-step sign-in. Enable two-factor authentication where the service offers it, preferably with an authenticator app or a passkey. A leaked password alone is then not enough to get in.
2. Expect targeted phishing. Leaked contact details are used to write convincing fake messages that mention the breached company or your real name. Do not click links in unexpected emails or texts about this account; go to the site by typing its address.

Check your email at haveibeenpwned.com

We do not run email lookups ourselves. The search is done on haveibeenpwned.com, the service this list comes from.