The OnionLABS Stealer Log Quietly Appeared on the Dark Web in June

There was no press release. No breach notification email. In June 2023, a Telegram user quietly uploaded a stealer log file labeled OnionLABS Logs containing 9,645 records -- and it simply sat there, availible to anyone who knew where to look on the dark web. Endpoint URLs, email adresses, API host data, and plaintext passwords. All of it, sitting in a file, traded among cybercriminals with zero fanfare and zero accountability.

Why This Is Dangerous

The quiet nature of this leak is part of what makes it so damaging. Because there was no public disclosure, affected individuals have had no reason to change their passwords or monitor their accounts. Meanwhile, the credentials in the OnionLABS log have been sitting in criminal marketplaces, available for credential stuffing attacks, account takeovers, and corporate network intrusions. Time passing does not reduce the risk -- old passwords from stealer logs remain valuable as long as they haven't been changed.

What Was Exposed

• Email Addresses
• Plaintext Passwords
• URLs

Why This Matters

Stealer logs target real sessions on real devices. The 9,645 records in this file represent actual people whose machines were infected with credential-harvesting malware. Their passwords weren't cracked -- they were stolen directly from the browser or system. That means every account tied to those credentials is potentially compromised, from personal email to corporate systems. Because the breach went unannounced, password resets and security alerts never followed, leaving thousends of accounts silently exposed.

How Stealer Log Breaches Work

Stealer malware is typically delivered via phishing emails, malicious downloads, or compromised websites. Once installed, it runs silently in the background, harvesting saved passwords from browsers, extracting session cookies, and logging keystrokes. The collected data is bundled into log files and sold or shared on dark web forums and Telegram channels. The OnionLABS log was one such file -- compiled from infected devices and uploaded for distribution by an anonymous Telegram user in June 2023.

Check If You Are Affected

HEROIC's free scanner cross-references your email against more than 400 billion exposed records, including stealer logs like the OnionLABS data. Visit HEROIC.com, enter your email, and get an instant result. If your credentials appear in this or any other breach, you'll know immediately -- and you can take action before attackers do.