Testing antivirus utilities with live malware can be risky. To minimize the possibility of damage during testing, I use virtual machines. When the test is done, I just revert the virtual machine to its clean, pre-test state. The Kure does something very similar to protect your PC. When you reboot, it restores the PC to a previous malware-free state, wiping out any changes except your own documents, pictures, and so on. And a ransomware-recovery feature reverses malicious changes to those documents.