Breach date: 2025-08-25. Added to this index: 2025-09-16. Accounts affected: about 870K. Domain: miljodata.se.
What happened
In August 2025, the Swedish system supplier Miljödata was the victim of a ransomware attack. Following the attack, data was subsequently published on the dark web and included 870k unique email addresses across various compromised files. Data also included names, phone numbers, physical addresses, dates of birth and government-issued personal identity numbers.
Breach data sourced from Have I Been Pwned, used under CC BY 4.0. Additional breach metadata provided by XposedOrNot. DataExposed is an independent service and is not affiliated with or endorsed by either.
What was exposed
Dates of birth: Your full birth date, day, month and year, collected at signup for age checks, identity verification, insurance quotes, birthday offers or government services.
Email addresses: The email address you used to register or log in. It is the most common field in breaches because it doubles as your username on most sites.
Genders: The gender or sex recorded on your profile, usually picked from a list at signup, sometimes with a title such as Mr or Ms or a gender identity option beyond male and female.
Government issued IDs: Numbers or images of official identity documents, such as passports, national identity cards, Social Security numbers, Medicare cards, tax file numbers, residence permits and voter cards.
Names: Your first name, surname and sometimes middle name or initials, as you gave them when you signed up. It appears in almost every breach because nearly every account asks for it.
Phone numbers: Your mobile or landline number, collected at signup for contact, delivery updates, marketing and two-factor codes.
Physical addresses: Your residential, postal, billing or delivery address, stored by retailers, utilities, banks, government services and almost any company that sends you something.
What to do now
Check whether your own address is in this dataset with the free email breach check.
Review the accounts connected to this service and turn on two-factor authentication.
Turn on two-factor authentication on your email account first, because it is the reset path for everything else.
Treat calls and messages that quote real details about you as hostile until you verify them another way.
Frequently asked questions
What data was leaked in the Miljödata breach?
The Miljödata breach exposed Dates of birth, Email addresses, Genders, Government issued IDs, Names, Phone numbers, Physical addresses. About 870K accounts were affected.
Was I affected by the Miljödata breach?
Run the free email breach check with the address you used on that service. It will tell you whether your address appears in this dataset.
What should I do about the Miljödata breach?
Treat any message that quotes details from this breach as suspicious, turn on two-factor authentication, and consider removing your details from people-search sites if your address or phone was included.