The Combo Mix 1 Leak Gave Attackers What They Need to Drain Accounts

HEROIC analysts identified a combolist labeled "Combo Mix 1" circulating on a Telegram channel in January 2023. The file paired 46,674 email addresses with plaintext passwords and the URLs of the sites those logins belong to, the standard format attackers use to automate login attempts across the web.

What the Combo Mix 1 Leak Gives Attackers

The name "Combo Mix" is a fitting one, this file blends credentials from multiple sources into one list formatted for immediate use. Because the passwords are stored in plaintext and paired with the URL of the site each one unlocks, an attacker does not need to guess or crack anything. They simply load the file into a login-testing tool and let it run against the matching sites automatically.

What Was Exposed

• Email addresses
• Plaintext passwords
• URLs linking each credential pair to its original login page

Why This Matters

With 46,674 credential pairs in one file, an attacker has more than enough volume to run a serious credential stuffing campaign. Anyone whose email and password appear here faces a real risk that a reused password elsewhere, banking, email, or shopping, gets tried and unlocked. Once an attacker gets into one account, they often use it to reset passwords elsewhere, turning a single leaked login into a much wider account takeover.

How Combolists Like This One Are Built

Combolists are compiled by merging credentials pulled from older breaches, phishing kits, and malware logs into a single searchable file, then formatted as email:password or email:password:URL so they can be fed straight into automated login tools. They are traded and sold cheaply on Telegram and dark web forums because they let low-skill attackers run large-scale login attempts with almost no technical effort. A file's age does not make it safe. Old combolists still work against anyone who has not changed the password since.

Check If You Are Affected

You do not have to guess whether your information is sitting in a dump like this one. HEROIC's free breach scanner checks your email address against more than 400 billion leaked records pulled from combolists, stealer logs, and dark web marketplaces. Run a free scan, and if a match turns up, change that password everywhere else you have used it.