If You Reuse Passwords, the Combo Mail-Pass Leak Should Worry You

In July 2026, HEROIC analysts found a combolist called Combo Mail-Pass circulating on Telegram. The file contained 1,125 records, each one pairing an email address with a plaintext password and the URL the login was tied to. Why the Combo Mail-Pass leak should concern you: if you've ever used the same password on more than one account, a leak like this is exactly the kind of file that puts you at risk. Attackers don't need to target you specifically, they run every email and password pair in this list against dozens of popular websites automatically, and any match becomes an open account. What was exposed in the Combo Mail-Pass file: email addresses, plaintext passwords, and URLs linked to each credential pair. Why reused passwords make this worse: if you reuse passwords, the 1,125 credential pairs in this file matter to you even if your specific account wasn't the original source. Attackers use combolists like this for credential stuffing, testing stolen logins across banking, email, and shopping sites in hopes that the same password unlocks more than one door. That's how a small leak turns into account takeover, identity theft, or direct financial fraud. How combolists like this get assembled: a mail-pass combolist is one of the simplest formats criminals trade, a plain text file listing email addresses and their matching passwords, one per line, gathered from older breaches or malware infections and repackaged for resale or free distribution on platforms like Telegram. Check if you are affected: if you reuse passwords across accounts, now is a good time to check your exposure. HEROIC's free breach scanner compares your email against more than 400 billion leaked records and tells you immediately if you're affected.