Breach date: 2020-06-21. Added to this index: 2022-11-22. Accounts affected: about 52M. Domain: not listed.
What happened
In 2020, a corpus of data containing almost a quarter of a billion records spanning over 400 different fields was misattributed to database marketing company Acxiom and subsequently circulated within the hacking community. On review, Acxiom concluded that "the claims are indeed false and that the data, which has been readily available across multiple environments, does not come from Acxiom and is in no way the subject of an Acxiom breach". The data contained almost 52M unique email addresses.
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
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.
IP addresses: The network addresses your devices used when you signed up, logged in or posted, recorded by almost every website in its access logs.
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 Not Acxiom breach?
The Not Acxiom breach exposed Email addresses, IP addresses, Names, Phone numbers, Physical addresses. About 52M accounts were affected.
Was I affected by the Not Acxiom 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 Not Acxiom 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.