If You Reuse Passwords, the Private ULP Leak Should Worry You

In December 2025, HEROIC analysts identified a combolist file circulating on Telegram, uploaded under the label Private_ULP_Leak_23.12.2025. The file contained 8,478,581 records pairing email addresses, plaintext passwords, and associated URLs, compiled from earlier breaches and packaged for cybercriminals to buy, trade, or use directly. Why this is dangerous: because the passwords in this file are stored in plaintext, anyone who obtains it can try the email and password pairs against other accounts immediately, with no cracking or decryption required. The URLs included alongside each pair often reveal exactly which site or service the credentials unlock, giving an attacker a direct route into accounts tied to your email address. What was exposed: email addresses, plaintext passwords, and associated URLs or login links. Why this matters: if you reuse the same password across multiple sites, a single leaked credential pair from this file could unlock your email, banking, or social media accounts. Combolists like this one are routinely used for credential stuffing attacks, where automated tools test stolen logins against hundreds of services at once, leading to account takeover, identity theft, and financial fraud. How combolists work: a combolist is a compiled text file that pairs usernames or email addresses with passwords, gathered from multiple earlier breaches or malware infections and merged into one master list. Criminals build and circulate these files on Telegram channels and dark web marketplaces because they save the work of hunting down credentials one breach at a time, and once a combolist leaks it can circulate indefinitely. Check if you are affected: with over 400 billion records in its database, HEROIC's free breach scanner can tell you in seconds whether your email address appears in this leak or any other breach on record. If it does, HEROIC will show you exactly what data was exposed so you can change passwords and secure your accounts before someone else uses them against you.