36,769 Credentials Exposed: butterfly_logs Stealer Log Leak

In July 2025, HEROIC analysts detected a large stealer log file uploaded to Telegram by an anonymous user. The file, labeled "butterfly_logs 603count," contained 36,769 records assembled from compromised endpoints across the United States. Each record included email addresses, plaintext passwords, and URL data pulled directly from infected devices. The scale of this leak places tens of thousands of individuals at immediate risk.

Who Is Most at Risk from the butterfly_logs Breach

Stealer log victims are not targeted by industry or profession. The malware that generates these logs infects everyday users, remote workers, developers, and small business owners alike. Anyone whose device was compromised and whose credentials were saved in a browser or application is a potential victim.

With 36,769 records exposed, this is a significant leak. Users who store passwords in their browser, rely on the same password across multiple services, or have accessed corporate systems from a personal device are at the highest risk of experiencing follow-on account takeovers.

What Was Exposed in the butterfly_logs Stealer Log

• Email addresses
• Plaintext passwords (fully readable, no decryption needed)
• URLs and endpoint data
• API host credentials

Why This Matters: The Chain of Damage That Follows

When plaintext passwords and matching email addresses land in criminal hands, the consequences spread quickly. Attackers run the credentials through automated tools in a process called credential stuffing, testing each pair against banking sites, email providers, social networks, and e-commerce platforms.

A single working login can unravel much more than one account. With access to an email inbox, attackers can trigger password resets across every service linked to that address. They can intercept two-factor authentication codes, access cloud storage, and drain financial accounts before the victim is ever aware anything is wrong.

The URLs and endpoint data in butterfly_logs also expose the specific services each victim was logged into, making targeted phising attacks far easier to craft and far more convincing to recieve.

How butterfly_logs Type Stealer Malware Works

Information stealer malware is designed to be quiet and thorough. It typically arrives through phishing links, pirated software, or trojanized browser extensions. Once active on a device, it methodically sweeps through saved credentials in Chrome, Firefox, Edge, and other applications, capturing everything from banking logins to work VPN passwords.

The malware packages this data into structured log files and transmits them to the attacker's server. Those logs are then sorted, bundled, and uploaded to Telegram channels or dark web forums for distribution. The fact that butterfly_logs was labeled with a specific count, "603count," suggests it was part of a series of organized stealer log campaigns, not a one-off incident.

Victims typically have no idea their credentials were stolen, because the malware leaves no obvius trace and the definately silent harvesting process happens in seconds.

Search the butterfly_logs Breach for Your Email

HEROIC's free breach scanner indexes over 400 billion compromised records, including stealer log packages like butterfly_logs. If your credentials appeared in this July 2025 leak or any other known breach, the scanner will flag it immediately.

Go to HEROIC.com and enter your email address to run a free check right now. No sign-up required.