A major data breach may have exposed the passwords of over 183 million internet users.

According to cybersecurity expert Troy Hunt, it has claimed the breach, which occurred in April 2025, compromised millions of email accounts across major domains, including Google, Yahoo, and Outlook.

Hunt revealed that the stolen data amounts to 3.5 terabytes—equivalent to 875 full-length HD movies. The information has now been added to his well-known data breach database, Have I Been Pwned (HIBP), a website that allows users to check if their email accounts have been affected by security breaches.

The Australian expert explained that the passwords were not leaked in a single incident but through a collection of “stealer logs”, which he described as “a series of data files generated and compiled by malware.”

“Stealer logs are more of a firehose of data that's just constantly spewing personal info all over the place,” Hunt said in his blog. “Once the bad guys have your data, it often replicates over and over again via numerous channels and platforms.”

How to check if your Google account has been hacked

If you suspect that someone else may be using your Google Account, it’s crucial to act quickly:

  • Change your password immediately for your Google Account and for any other apps or websites where you used the same password.
  • Check connected apps and devices — remove any unfamiliar logins or devices.
  • Review saved passwords in your Google Account and update any that might have been reused elsewhere.

How to check it via Have I Been Pwned

Users are advised to visit haveibeenpwned.com and enter their email address to see if their accounts have been compromised.

The website checks against not only the latest breach but also previous incidents. Users whose details appear in the database are urged to change their passwords immediately and enable two-step authentication to strengthen their account security.

The April 2025 data breach added a staggering 183 million records, containing email addresses and passwords, to the Have I Been Pwned database. As Hunt noted in his blog, this dataset stands out because of its volume and the variety of sources it draws from, making it one of the most significant leaks of the year.