The "107K" designation usually indicates the approximate number of records (107,000) contained within the file. Similar files, like 15K Mix.txt , have been flagged by security monitoring platforms as containing leaked credentials.
The data is rarely from a single new breach. Instead, it is a compilation of information from older leaks, "stealer logs" (data harvested by infostealer malware), and phishing campaigns. 107K MIX.txt
Some datasets of this nature are derived from infostealers , which are malicious programs that secretly collect logins and browser data from infected devices. Recommended Actions If you suspect your information may be in such a file: like 15K Mix.txt
Immediately update passwords for any accounts that used the leaked credentials. 107K MIX.txt