If You Have German Accounts, This 1.3M Password Leak Matters

In late January 2023, HEROIC analysts flagged a stealer log posted to Telegram under the name "1.3KK Germany DE UserPass Mix," containing 1,305,861 exposed records tied to German users. Each record pairs an email address with a plaintext password and the URL of the site that login belongs to, the fingerprint of infostealer malware that harvests saved credentials directly off a victim's device.

If You Reuse Passwords, This Leak Should Worry You

Over 1.3 million username and password combinations is enough volume that automated tools can test every single one against major email, banking, and shopping sites within hours. If you are in this dataset and you reuse passwords across accounts, an attacker does not need to guess anything, they already have a working password and the exact web address to try it on.

What Was Exposed in the UserPass Mix

• Email addresses
• Plaintext passwords
• URLs of the associated login pages

Why This Matters

A file this size is built for credential stuffing at scale. Attackers load lists like this into automated login bots that quietly try each pair against dozens of popular websites. Anyone whose password shows up here is exposed to account takeover on every other site where they used the same password, and from there, identity theft and financial fraud become real possibilities.

How This Stealer Log Was Built

Stealer malware typically spreads through cracked software, fake installers, or malicious email attachments. Once it infects a machine, it silently copies every password saved in the browser, along with the site it belongs to, and sends it back to the attacker. Over time these logs get merged into massive combined files like this 1.3 million record mix, then traded or sold in Telegram groups dedicated to stolen data.

Check If You Are Affected

With over 1.3 million records in this single file, the odds that your email is in there are worth taking seriously. HEROIC's free breach scanner checks your email against a database of more than 400 billion compromised records, including leaks like this one, so you can find out in seconds and change any reused passwords before someone else uses them first.