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Data breaches → McGraw Hill

Was your data in the McGraw Hill breach?

2026 · mheducation.com · ~13,500,136 accounts exposedCritical severity · 8/10

McGraw Hill (mheducation.com) suffered a data breach in 2026 that exposed around 13,500,136 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 April 2026, education company McGraw Hill confirmed a data breach following an extortion attempt. Attributed to a Salesforce misconfiguration, the company stated the incident exposed "a limited set of data from a webpage hosted by Salesforce on its platform". More than 100GB of data was later publicly distributed, containing 13.5M unique email addresses across multiple files, with additional fields such as name, physical address and phone number appearing inconsistently across some records.

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 McGraw Hill breach exposed and what each item actually enables:

Home 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.

Phone numbers

Enables SIM-swap attacks (hijacking your number to intercept SMS codes), smishing, and voice scams that appear to come from your bank.

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.

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. Home addresses: Get your address removed from data brokers — they re-list roughly every four months, so this needs repeating.
  2. Phone numbers: Move two-factor authentication off SMS to an authenticator app or passkey, and add a port-out PIN with your mobile provider.
  3. Names and usernames: Search your usual username to see what else it exposes, and use distinct handles for sensitive accounts.
  4. Email addresses: Treat any message referencing this service with suspicion, and never act on links in unexpected emails.
  5. 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 McGraw Hill 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 recent, so the data is actively traded and the risk is at its highest right now.

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 McGraw Hill — 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 McGraw Hill breach?

The McGraw Hill breach exposed home addresses, 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 McGraw Hill breach?

Around 13,500,136 accounts were exposed, making it a very large breach by any measure.

What should I do if I had a McGraw Hill 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 McGraw Hill breach affected you, these breaches exposed comparable information — worth checking too, since leaked datasets are routinely combined.

See all breaches we cover →