The contents typically consist of massive plain text files organized into a simple, machine-readable format: : Usually email:password or username:password .
A "combolist" (short for "combination list") like is a compressed archive containing nearly a million sets of stolen user credentials. These files are primary tools in cyberattacks and are frequently traded or leaked on dark web forums and Telegram channels. Standard Content and Format 997K COMBOLIST.rar
The primary purpose of a combolist is to facilitate automated cyberattacks: Combolists and ULP Files on the Dark Web - Group-IB The contents typically consist of massive plain text