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Data breaches → MDPI

Was your data in the MDPI breach?

2016 · mdpi.com · ~845,012 accounts exposedCritical severity · 8/10

MDPI (mdpi.com) suffered a data breach in 2016 that exposed around 845,012 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 August 2016, the Swiss scholarly open access publisher known as MDPI had 17.5GB of data obtained from an unprotected Mongo DB instance. The data contained email exchanges between MDPI and their authors and reviewers which included 845k unique email addresses. MDPI have confirmed that the system has since been protected and that no data of a sensitive nature was impacted. As such, they concluded that notification to their subscribers was not necessary due to the fact that all their authors and reviewers are available online on their website.

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 MDPI breach exposed and what each item actually enables:

Private messages

Personal correspondence can be used for blackmail or social engineering, and often contains other sensitive details you have forgotten sharing.

Names and usernames

Links this leak to your other accounts — a reused username lets anyone build a profile of you across platforms.

Email addresses

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.

IP addresses

Reveals your approximate location and internet provider, which adds credibility to targeted scams.

What to do if you were affected

These steps are ordered for this specific breach — the most urgent action given what leaked comes first.

  1. Private messages: Consider what was discussed on this service and whether anything needs changing (shared passwords, personal disclosures).
  2. Names and usernames: Search your usual username to see what else it exposes, and use distinct handles for sensitive accounts.
  3. Email addresses: Treat any message referencing this service with suspicion, and never act on links in unexpected emails.
  4. IP addresses: No direct action needed, but be wary of anyone quoting your location as “proof” of identity.
  5. Check whether your own email appears in this breach — run a free scan to confirm before you spend time on the steps above.

How urgent is this now?

This breach is over 10 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.

Check if your email was exposed.Nullivo's free scan checks your own verified email against known breaches — including MDPI — in 30 seconds. No password, no signup, and we only ever scan your own email. Run your free scan →

Frequently asked questions

What data was exposed in the MDPI breach?

The MDPI breach exposed private messages, names and usernames, email addresses, ip addresses. Personal correspondence can be used for blackmail or social engineering, and often contains other sensitive details you have forgotten sharing.

How many people were affected by the MDPI breach?

Around 845,012 accounts were exposed, making it a mid-sized breach.

What should I do if I had a MDPI account?

Consider what was discussed on this service and whether anything needs changing (shared passwords, personal disclosures). 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 MDPI breach affected you, these breaches exposed comparable information — worth checking too, since leaked datasets are routinely combined.

See all breaches we cover →