Breach date: 2016-12-16. Added to this index: 2016-12-20. Accounts affected: about 16K. Domain: ethereum.org.
What happened
In December 2016, the forum for the public blockchain-based distributed computing platform Ethereum suffered a data breach. The database contained over 16k unique email addresses along with IP addresses, private forum messages and (mostly) bcrypt hashed passwords. Ethereum elected to self-submit the data to HIBP, providing the service with a list of email addresses impacted by the incident.
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.
Passwords: The secret you use to sign in, stored by the breached service either in plain text, in a scrambled form called a hash, or encrypted. How it was stored decides how quickly it can be recovered.
Private messages: Direct messages, chats and inbox conversations on a platform, which can include photos, links, attachments, addresses, phone numbers and details you shared expecting only one person to read.
Usernames: The handle or login name you chose for an account, which may be public on forums, games and social platforms or used privately to sign in.
Website activity: Records of your actions on a website or app, such as pages viewed, searches, clicks, downloads, logins, cart activity, IP addresses and timestamps.
What to do now
Check whether your own address is in this dataset with the free email breach check.
Change the password on this service and every other site where you used the same password.
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 Ethereum breach?
The Ethereum breach exposed Email addresses, IP addresses, Passwords, Private messages, Usernames, Website activity. About 16K accounts were affected.
Was I affected by the Ethereum 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 Ethereum breach?
Change the password on that account and everywhere you reused it, then turn on two-factor authentication. Passwords from this breach are traded and tried automatically against other sites.