Many sites claiming to offer "free combo lists" are actually honey pots. The .txt file you think you are downloading might actually be an .exe or a script designed to install a keylogger on your machine.
A "combo" list (short for combination list) is a simple text file containing thousands—sometimes millions—of username/email and password pairs. These lists are usually formatted as email:password or username:password .
The allure of a "125K Combo txt" download is often tied to the "easy" side of cyber-entry, but it is a path fraught with security risks and ethical dilemmas. If you are a developer or a security enthusiast, focus on building defenses rather than collecting old, stolen data. Stay safe, stay legal, and keep your passwords unique.
Instead of seeking out these lists, you should focus on ensuring your information isn't on them.
White-hat hackers and researchers use them to test the strength of their own systems or to see if their own emails have been compromised. The Dangers of Downloading These Files
Ensure every site you use has a unique, complex password. This way, if one site is breached, your other accounts remain safe. Final Thoughts
Instead of downloading a suspicious txt file, use Have I Been Pwned to see if your email has appeared in any known breaches.