Is Your Password in the Microsoft 10 Stealer Log Leak? Check Now

In early May 2026, HEROIC analysts identified a stealer log file labeled "Microsoft 10," uploaded to a Telegram channel by an unidentified user. The file exposed 1,137 records pairing email addresses with plaintext passwords and the URLs of the login pages they were captured from, likely including Microsoft account sign-in pages, gathered from devices infected with information-stealing malware. If you use a Microsoft account, this is worth checking.

Why This Should Concern You

This isn't a breach of Microsoft's own servers, it's a batch of stolen logins pulled from infected devices and labeled "Microsoft 10" because of the sign-in pages involved. If your credentials are among the 1,137 exposed, an attacker doesn't have to guess where your password works, it's already paired with the exact URL. And because the passwords are stored in plaintext, anyone who gets the file can try your login immediately, no cracking needed.

What's in the Microsoft 10 Leak

• 1,137 email addresses used as account logins
• Plaintext passwords tied to each email
• The URLs of the login pages, apparently including Microsoft account portals, each credential unlocked

Why You Should Care Even If You Don't Recognize This Leak

You may never have heard of "Microsoft 10" before today, and that's normal, stealer logs are usually never announced to their victims. If your email and password are in this file and you've reused that password on other accounts, attackers can use it for credential stuffing, account takeover, or to access anything tied to your Microsoft account, including email, cloud files, and connected apps.

How a Log Like This Ends Up on Telegram

Stealer logs come from malware that infects your device, often through a malicious download, cracked software, or phishing link, then quietly copies the usernames, passwords, and URLs saved in your browser. That data is bundled into a file and sent back to whoever controls the infection. From there, it's commonly sold, traded, or, as with this file, uploaded to a Telegram channel where anyone can download it.

Find Out If You're One of the 1,137

You don't have to wonder. HEROIC's free breach scanner checks your email address against more than 400 billion leaked records, including stealer logs like this one. If you turn up in the Microsoft 10 leak or any other breach, you'll get clear steps to lock down your accounts. Run a free scan now to see where you stand.