The ‘usysssss’ Leak Has Nearly as Many Records as Toledo, Ohio

What HEROIC Analysts Found

On May 24, 2026, HEROIC analysts identified a combolist file uploaded to a Telegram channel under the name "usysssss." The file contained 269,628 records pairing email addresses with plaintext passwords and the website URLs those credentials were tied to. That is a large enough set of records to roughly match the population of a mid-sized American city like Toledo, Ohio, all packaged into a single file traded in a private Telegram group.

Why This Is Dangerous

Because the passwords in the usysssss file are stored in plaintext and matched directly to the site each one came from, an attacker does not need to crack or decode anything before using them. At this scale, automated tools can run through all 269,628 credential pairs against target sites in a matter of hours, turning one leaked file into hundreds of thousands of attempted account takeovers.

What Was Exposed

• Email addresses
• Plaintext passwords
• Associated website URLs

Why This Matters

A file the size of usysssss is exactly what credential stuffing attacks are built around: automated software that tries stolen email and password pairs across many websites at once, hunting for reused logins. If any of the 269,628 people in this leak reused a password on a bank, email account, or online store, that account is exposed to takeover. From there, attackers can drain financial accounts, lock the real owner out of their own email, or use stolen personal information to commit identity theft.

How Combolist Leaks Work

A combolist pairs a username or email with a password, typically formatted as "email:password" on each line, and is usually built by merging data from older breaches, stealer logs, and prior leaks rather than a single fresh hack. Large combolists like usysssss are prized in criminal circles precisely because of their size, since more records mean a higher chance that at least some of the credentials still work somewhere.

Check If You Are Affected

If you think your email could be part of the usysssss leak or any other exposure, HEROIC's free breach scanner checks your information against a database of more than 400 billion leaked records. Run a free scan to see if your credentials appeared in this leak and get clear guidance on what to change.