A data breach broker is selling the user information of 25 million people who have used the website Mathway and who still have active accounts there.

Mathway is an online calculator that offers people the chance to do math with a calculator without having to sign up, but they also offer the chance to create a user account to the site.

In addition to being a website, Mathway has a top-rated app on mobile platforms. It’s ranked as high as fourth for educational apps on Apple’s App Store.

An intelligence firm named Cyble from cyble.io has revealed that they were tracking a data breach at Mathway after they had heard the news of the database breach being sold on a dark web market place for $4,000.

What makes information such as these database breaches so valuable is that often people use the same passwords across multiple domains. Thus, if your details are in Mathway and they’re the same as you use on other websites, you will want to change your passwords as soon as possible.

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