Breach date: 2015-05-22. Added to this index: 2017-03-27. Accounts affected: about 501K. Domain: bitcointalk.org.
What happened
In May 2015, the Bitcoin forum Bitcoin Talk was hacked and over 500k unique email addresses were exposed. The attack led to the exposure of a raft of personal data including usernames, email and IP addresses, genders, birth dates, security questions and MD5 hashes of their answers plus hashes of the passwords themselves.
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.
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.
Security questions and answers: The questions and answers used to verify you during password resets or phone support, such as your first pet, first school, favourite teacher or mother's maiden name.
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 Bitcoin Talk breach?
The Bitcoin Talk breach exposed Dates of birth, Email addresses, Genders, IP addresses, Passwords, Security questions and answers, Usernames, Website activity. About 501K accounts were affected.
Was I affected by the Bitcoin Talk 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 Bitcoin Talk 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.