NemoWeb data breach

Breach date: 2016-09-04. Added to this index: 2018-09-19. Accounts affected: about 3.5M. Domain: nemoweb.net.

What happened

In September 2016, almost 21GB of data from the French website used for "standardised and decentralized means of exchange for publishing newsgroup articles" NemoWeb was leaked from what appears to have been an unprotected Mongo DB. The data consisted of a large volume of emails sent to the service and included almost 3.5M unique addresses, albeit many of them auto-generated. Multiple attempts were made to contact the operators of NemoWeb but no response was received.

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.
  • 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.

What to do now

  1. Check whether your own address is in this dataset with the free email breach check.
  2. Review the accounts connected to this service and turn on two-factor authentication.
  3. Turn on two-factor authentication on your email account first, because it is the reset path for everything else.
  4. 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 NemoWeb breach?

The NemoWeb breach exposed Email addresses, Names. About 3.5M accounts were affected.

Was I affected by the NemoWeb 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 NemoWeb 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.

Next steps