What Is a Stealer Log? BLACKHATCLOUD ULP Leak Shows 132,174 Cases

If you have never heard the term stealer log before, the BLACKHATCLOUD ULP leak from July 3, 2025 is a good, if unfortunate, example of exactly what one looks like. This file, uploaded to Telegram, contains 132,174 records of email addresses, plaintext passwords, and URLs, all pulled from devices infected with information stealing malware.

Why This Is Dangerous

A stealer log is dangerous precisely because of how complete it is. Unlike an old fashioned password dump that might just list usernames and hashed passwords, a stealer log includes the plaintext password and the exact site it belongs to, all harvested directly from the victim's own browser. There is nothing left for an attacker to guess.

What Was Exposed

• Email addresses used as account logins
• Plaintext passwords with zero encryption
• URLs showing which accounts and sites are affected
• 132,174 total records found in the file

Why This Matters

Understanding what a stealer log actually is matters because it changes how seriously you should take a leak like this one. This isn't a company's server getting breached, it's individual computers getting infected one at a time untill the combined results reach a number like 132,174. That distinction matters because it means the fix starts with each person's own device security, not just a company password reset.

How Stealer Logs Work

A stealer log is created by malware, often called an infostealer, that infects a computer through a cracked program, fake update, or malicious attachment. The malware then quietly copies every password saved in the browser along with cookies and autofill data, before sending it all back to the person controlling the infection. That data eventually gets compiled and posted publically, exactly like the BLACKHATCLOUD ULP file did.

Check If You Are Affected

Now that you know what a stealer log is, the next step is finding out if you are in one. HEROIC's free breach scanner checks your email against more than 400 billion leaked records, covering stealer logs, combolists, and traditional breaches alike, so you get a complete picture in one search.