If You Reuse Passwords, the 63 Boss Leak Should Worry You: 2,875 Records Exposed

In June 2023, HEROIC researchers captured and indexed a stealer log file uploaded to Telegram by a threat actor using the handle 63 Boss. The dataset contained 2,875 records, each containing an email address, a plaintext password, and the URL of the service that was targeted when the malware was running on the victim's device. This data was not stolen from a company's servers. It was taken directly from individuals' machines by information-stealing malware operating silently in the background, then distributed through a Telegram channel accessible to anyone who knew where to look.

Why This Is Dangerous

The 63 Boss dump contains credentials that were live and working at the moment of theft. This is what separates stealer log data from older database leaks. There is no hashing, no encryption, no aging. Attackers who download this file can immediately test these email and password pairs against banking sites, email providers, and online retailers. The service URLs bundled with each credential tell them exactley which platform to target first, removing the guesswork from account takeover and enabling precise, automated attacks at scale.

What Was Exposed

• Email Addresses
• Plaintext Passwords
• URLs (specific service endpoints targeted during the malware infection)

Why This Matters

If your browser saves your passwords and you have ever clicked a phishing link, downloaded unverified software, or installed an untrusted browser extension, your credentials could appear in a stealer log. The 63 Boss dump represents 2,875 people who experienced exactly that. When your email and password are available in plaintext, attackers can test them accross every major platform simultaneously. One compromised login becomes a pivot point for identity theft, financial fraud, and takeover of your other accounts through password reset flows. The seperate platforms you use are all at risk when a single shared password is exposed.

How Stealer Logs Work

Stealer malware is a type of credential-harvesting software designed to extract passwords from your device without your knowledge. It is typically delivered through phishing emails, fake software downloads, or malicious browser extensions. Once installed, it enumerates your browser's saved credentials, session cookies, and autofill data, packages everything into a compressed archive, and silently sends it to the attacker. The 63 Boss operator collected these archives from multiple infected devices and published the resulting bundle to Telegram. Because the entire process occured on victims' own devices rather than at a service provider, no corporate breach disclosure was triggered. Victims had no way to recieve a warning that their credentials had been stolen.

Check If You Are Affected

If you reuse passwords, the 63 Boss stealer log should concern you. HEROIC's free breach scanner checks your email address against more than 400 billion compromised records, including this stealer log dataset and thousands of others. A single search takes seconds and will tell you whether your adress appeared in the 63 Boss dump or any other indexed breach. Search now to find out if your credentials were stolen and take action before attackers use them against you.