How the Combo Stealer Log Leaked 269,835 Logins to Telegram

How the Combo Stealer Log Reached Telegram

On December 10, 2022, HEROIC analysts traced a stealer log file, labeled "Combo," to a user distributing it on Telegram. The file held 269,835 records, each combining an email address with a plaintext password and the web address the login was used on. Files like this are commonly called "combo lists" because they combine credentials pulled from many different infected devices into one large, sellable collection.

Why This Is Dangerous

Because the passwords in this file were never encrypted or hashed, they can be read and used the moment someone opens the log, with no extra effort required. Pairing each password with the exact site it was used on makes the data even more useful to an attacker, since it removes the guesswork of figuring out where a stolen login might work. With nearly 270,000 entries, the file gives whoever holds it a large, ready-made target list to work through.

What Was Exposed

• Email addresses
• Plaintext passwords
• Website login URLs tied to each credential

Why This Matters

A leaked email and password combination rarely stays contained to one account. Because so many people reuse passwords across multiple sites, attackers often take combo lists like this one and run them through automated tools that test each pair against banking sites, email providers, and online retailers. When a password matches, the result can be a hijacked account, unauthorized charges, or an attacker using the compromised inbox to reset passwords on other services entirely.

How Stealer Logs Work

Combo lists like this one start as separate stealer logs, each produced by infostealer malware running on an individual infected computer. The malware quietly pulls saved usernames and passwords out of the browser, sometimes along with cookies or autofill details, then sends everything back to whoever controls it. Criminals frequently combine many of these individual logs into a single large file, which is what turns a batch of small infections into a combo list of hundreds of thousands of records. These combined files are then traded or sold through channels like Telegram, where other criminals can pick them up.

Check If You Are Affected

With close to 270,000 credentials in circulation, it is worth checking whether your information is part of this list. HEROIC's free breach scanner searches more than 400 billion leaked records, including stealer logs and combo lists like this one, to tell you if your email address has appeared anywhere it shouldn't. Run a free scan, and if you get a match, change that password right away and turn on multi-factor authentication wherever it is available.