A "combolist" is a text file containing pairs of usernames and passwords (e.g., user@email.com:password123 ).
If you encountered this file as a downloadable link from an untrusted source, do not open it . Files like this are frequently used to distribute malware or spyware , especially if they are bundled in .zip or .rar archives. You can check if your email was part of a major breach using tools like Have I Been Pwned . 150k MustHave USA.txt
Filenames like this are common in "combolists" found on the dark web or credential-sharing forums. A "combolist" is a text file containing pairs