The 12k UHQ Yahoo Contains 10,023 Stolen Email and Password Pairs

HEROIC analysts identified this stealer log on 05-Jan-2023. The breach exposed 10,023 records, with stolen data including email addresses, plaintext passwords, and URLs. The source is identified as 12k UHQ Yahoo.

Why This Is Dangerous

The 12k UHQ Yahoo stealer log collected Yahoo login credentials directly from infected devices, giving attackers 10,023 plaintext email and password pairs. Because Yahoo accounts are linked to financial services, news subscriptions, and email communications, a successful account takeover using these credentials can expose years of private correspondence and personal information. The inclusion of URLs in this log means attackers know exactly which accounts were targeted.

What Was Exposed

• Email Addresses
• Plaintext Passwords
• URLs

Why This Matters

Ten thousand credentials focused on a single email provider represent a concentrated attack surface. Criminals can use automated tools to test all 10,023 Yahoo login pairs rapidly, then pivot to associated accounts that share the same email address and password. Anyone who has not changed their Yahoo password since January 2023 may still be at risk from this breach.

How a Stealer Log Works

A stealer log is created when malware infects a device and silently copies saved browser passwords, login URLs, and session data. That information is packaged into a file and shared through underground Telegram channels, where criminals use it to attempt unauthorized logins at scale. The 12k UHQ Yahoo log is one example of this type of credential theft.

Check If You Are Affected

HEROIC offers a free breach scanner that searches 400 billion records from known breaches. Search your email address now to find out if your credentials appear in this breach or others. The scan is free and takes seconds.