Malware? renames my library files

something is re-naming my library files to EVO which is the name of a person providing files. A detailed virus scan of the disk shows nothing. I have to delete and rebuild my library to get rid of the 30 or more name changes.

I’ve had this happen to me twice now in the public folder but with caleb ransomware. All my computers have up to date virus scanners and are running Malwarebytes, also my recent full scans show no infections, Yet this keeps happening.

Why???