Data breaches → Wiener Büchereien
Was your data in the Wiener Büchereien breach?
2019 · ~224,119 accounts exposedCritical severity · 8/10
Wiener Büchereien suffered a data breach in 2019 that exposed around 224,119 accounts. If you had an account, some of your personal data may be circulating in leaked databases. The fastest way to know is to check your own email — free, in about 30 seconds, no password required.
What happened
In June 2019, the library of Vienna (Wiener Büchereien) suffered a data breach. The compromised data included 224k unique email addresses, names, physical addresses, phone numbers and dates of birth. The breached data was subsequently posted to Twitter by the alleged perpetrator of the breach.
Breach details sourced from Have I Been Pwned, the industry-standard breach database. Risk analysis by Nullivo.
What was exposed, and why it matters
Not all breaches carry the same risk — what matters is which fields leaked. Here is what the Wiener Büchereien breach exposed and what each item actually enables:
Home addresses feed people-search and data-broker sites, which republish them publicly. They also make phishing far more convincing and, in the worst cases, enable real-world harassment.
Date of birth is a permanent identifier used to verify identity by phone. Combined with a name and address it is often enough to impersonate you.
Enables SIM-swap attacks (hijacking your number to intercept SMS codes), smishing, and voice scams that appear to come from your bank.
Links this leak to your other accounts — a reused username lets anyone build a profile of you across platforms.
Puts you on spam and phishing lists, and confirms to attackers that you hold an account with this service — which makes impersonation emails more believable.
What to do if you were affected
These steps are ordered for this specific breach — the most urgent action given what leaked comes first.
- Home addresses: Get your address removed from data brokers — they re-list roughly every four months, so this needs repeating.
- Dates of birth: Never confirm your date of birth to an inbound caller — hang up and dial the organisation back on a published number.
- Phone numbers: Move two-factor authentication off SMS to an authenticator app or passkey, and add a port-out PIN with your mobile provider.
- Names and usernames: Search your usual username to see what else it exposes, and use distinct handles for sensitive accounts.
- Email addresses: Treat any message referencing this service with suspicion, and never act on links in unexpected emails.
- Check whether your own email appears in this breach — run a free scan to confirm before you spend time on the steps above.
This breach put your details on data-broker sites
Because Wiener Büchereien exposed home addresses, this is one of the breaches that feeds people-search and data-broker sites. Those sites scrape leaked databases, combine them with public records, and republish the result as a searchable profile — which is how a single breach turns into a permanent public listing. Removal works, but brokers typically re-list within about four months, so it has to be repeated.
See our broker-by-broker removal guides →
How urgent is this now?
This breach is over 7 years old. Old credentials still cause harm — leaked passwords from a decade ago are still tried against new accounts every day.
Remember: a breach can't be "un-leaked" — once a database is out, it exists in countless copies. The goal is to make the leaked data useless: change what can be changed, lock down what can't, and remove what has been republished.
Frequently asked questions
What data was exposed in the Wiener Büchereien breach?
The Wiener Büchereien breach exposed home addresses, dates of birth, phone numbers, names and usernames, email addresses. Home addresses feed people-search and data-broker sites, which republish them publicly. They also make phishing far more convincing and, in the worst cases, enable real-world harassment.
How many people were affected by the Wiener Büchereien breach?
Around 224,119 accounts were exposed, making it a mid-sized breach.
What should I do if I had a Wiener Büchereien account?
Get your address removed from data brokers — they re-list roughly every four months, so this needs repeating. You can check whether your own email appears in this breach with a free Nullivo scan — no password required.
Breaches that exposed similar data
If the Wiener Büchereien breach affected you, these breaches exposed comparable information — worth checking too, since leaked datasets are routinely combined.
- Was your data in the Utair breach? (2019, ~401,400 accounts)
- Was your data in the Royal Enfield breach? (2019, ~420,873 accounts)
- Was your data in the Youthmanual breach? (2019, ~937,912 accounts)
- Was your data in the People's Energy breach? (2020, ~358,822 accounts)
- Was your data in the HTH Studios breach? (2018, ~411,755 accounts)
- Was your data in the University of California breach? (2020, ~547,422 accounts)