Our Analysts Found the CZECHIA Combolist With 331,138 Leaked Accounts

HEROIC analysts discovered a large combolist labeled "CZECHIA" circulating on Telegram in June 2026. The file contained 331,138 records, each combining an email address with a plaintext password and the URL of the site it was used on, making it one of the larger uploads our team has flagged recently in this category.

Why This Is Dangerous

With over 331,000 records in plaintext, this is a large-scale credential list ready for immediate use. There is no encryption to break and no verification needed by the attacker, just a straightforward attempt to log into each account listed. The sheer size of the file means automated tools can work through it quickly, testing thousands of logins in minutes.

What Was Exposed

• Email addresses
• Plaintext passwords
• Associated login URLs

Why This Matters

A combolist of this size dramatically increases the odds that credential stuffing attacks will succeed somewhere. Even a small percentage of password reuse across 331,138 accounts translates into a meaningful number of compromised logins elsewhere, potentially including banking, email, and shopping accounts far removed from wherever this data originally came from — the ingredients for account takeover, identity theft, and financial fraud at scale.

How Combolists Work

Combolists are assembled from a mix of older breaches, phishing campaigns, and malware-infected devices, then combined into a single file and often labeled by region, keyword, or theme before being shared. The "CZECHIA" label on this file suggests the records were grouped or filtered around that theme before being uploaded, though the underlying credentials may still originate from many different, unrelated sources.

Check If You Are Affected

With over 331,000 records involved, the odds that your information is part of this leak are worth taking seriously. HEROIC's free breach scanner checks your email against more than 400 billion exposed records in seconds. Run a scan today and update any password you recognize.