Rabbit.7z.001 -

Signifies this is the first volume of a multi-part set.

If you found this file on your system unexpectedly, follow these precautions: How to Extract .7z.001 files - Microsoft Q&A RABBIT.7z.001

It encrypts local files and modifies the Master Boot Record (MBR) to display a ransom note upon reboot, effectively locking the entire system. Signifies this is the first volume of a multi-part set