How 16.3 Million Mathway Logins Ended Up in a Telegram File

16,365,590. That is the number of records HEROIC analysts logged from a file named mathway.com, tied to logins for the math help site and app, uploaded to Telegram on November 28, 2020. Each record pairs an email address with a plaintext password and the URL of the login page it belonged to.

Why This Is Dangerous

A file this large usually means a wide slice of a service's everyday users, students and anyone else who relied on the site to check homework, not a narrow or unusual group. With 16,365,590 plaintext passwords ready to use, the sheer volume is what turns this into a serious credential stuffing resource.

What Was Exposed

• Email addresses, the identifier used to match this record to a person's other accounts
• Plaintext passwords, readable and usable exactly as written, with no cracking needed
• URLs, pointing back to the Mathway login page each pair belonged to

Why This Matters

Students and casual users often reuse a simple password across a homework app, an email account, and other everyday logins without thinking twice, and a file at this scale means that habit is now working against millions of people at once. A leaked Mathway password is only the starting point for wherever else that same password unlocks a door.

How This Breach Type Works

This record set is a combolist, meaning it was compiled from existing email and password pairs pulled together from earlier leaks or scraped data rather than captured live during an active intrusion. Once a file this size lands on Telegram, it gets fed straight into automated credential stuffing tools that work through millions of pairs, testing each one against a wide range of other sites.

Is Your Old Mathway Password Still in Use?

Run a scan your email to check your address against this file and others like it. If the password shown still protects any account you use today, change it now and turn on multi-factor authentication wherever it is available. Check a work email in addition to a personal one, since a file of this size is likely to include both.