3,516 Credentials from Mixed_Leak_20250623 Found on Dark Web

HEROIC's dark web monitoring detected a stealer log known as Mixed_Leak_20250623 circulating on underground channels. This breach exposed 3,516 records containing sensitive authentication data harvested from infected devices by infostealer malware.

The Danger of Plaintext Passwords in This Breach

Every password in the Mixed_Leak_20250623 data set was stored in plaintext, meaning attackers can use them immediately without any cracking effort. Plaintext passwords give cybercriminals instant access to accounts, allowing them to move quickly before victims even realize they have been compromised. If you reuse passwords across services, a single plaintext exposure can cascade into breaches across your entire digital life.

What Was Exposed

• Email Addresses — used as login identifiers and for phishing campaigns
• Plaintext Passwords — immediately usable credentials with no decryption needed
• URLs — the specific websites and services victims were logged into when compromised

How Credential Stuffing Puts You at Greater Risk

Attackers take the email and password combinations from this breach and systematically test them against hundreds of popular websites, banking platforms, and cloud services. This technique, known as credential stuffing, exploits the common habit of password reuse. Even a single match gives an attacker a foothold that can lead to identity theft, financial fraud, or further account takeovers.

Understanding Stealer Logs and Infostealer Malware

This breach originated from stealer logs, which are files generated by infostealer malware silently running on victims' devices. These malicious programs capture saved browser passwords, session cookies, autofill data, and other sensitive information, then transmit it back to threat actors. Stealer logs are especially dangerous because they capture credentials exactly as they are used, bypassing traditional security measures like hashing.

Check If Your Credentials Were Exposed

HEROIC maintains one of the world's largest databases of compromised credentials with over 400 billion records sourced from breaches, stealer logs, and dark web leaks. Use HEROIC's free breach scanner to instantly check whether your email address or password appeared in the Mixed_Leak_20250623 data set or any other known breach.