Hackers use these lists to automatically test the same email/password on other sites (e.g., banking, social media).

Check for "Sent" items you didn't write or "Read" statuses on emails you haven't opened.

This type of database is highly valuable to cybercriminals because "mail access" provides more than just a login; it grants entry to the core of a user's digital identity.

Adding MFA is the most effective way to prevent unauthorized access even if the password is leaked.

Change the password for the affected email account and any other accounts using the same or similar passwords.

The subject line refers to a specific data leak posted on a cybercrime forum by a threat actor known as Old_Deep . This specific leak was distributed on February 3, 2023, and contains approximately 100,000 sets of compromised email credentials, designed for "mail access"—meaning the credentials allow direct login to the mailboxes themselves. Incident Overview Source: A cybercrime forum or "dark web" marketplace. Leak Name: 100K HQ MAIL ACCESS BASE. Threat Actor: Old_Deep. Release Date: February 3, 2023.