I use a top rated anti-malware program together a specialty anti-ramsomware program (Bitdefender and Malwarebytes). However until now my backups have not been done regularly or in an organized fashion. Some are on internal drives (but the power for which is controlled by a mechanical switch on a PCI card so they can and are powered off unless needed, some are on external USB drives and some on drives on other computers at offsite locations. I used to backup to the cloud, but stopped.
I recently setup a Linux SFTP server. I would like to schedule regular unattended weekly backups during the night, but my concern is that this necessitates that I would have to give the backup program the SFTP logon info and ransomware could somehow discover my logon credentials and password and encrypt the files on the SFTP server as well. (I am unclear how often PCs running Linux are infected with ransomware.)
I am unclear as to how ransomware programs gain access to backups in the cloud. or other NAS.
I was thinking I could minimize the time I was exposed to a ransomware attack by running the backup program off a USB drive that remained disconnected except on the scheduled backup night, or alternately have the backup program run and save temporary backup files on a VeraCrypt encrypted drive (setup so it does not have a drive letter available to Windows) so it would hopefully remain unencrypted unless the vault was opened which would only be on the scheduled backup night. Also on that night I would possibly switch from an administrator account to a non-admin one that would require USER control.
I would prefer not to have to plug a drive in, open a vault, or switch to a USER account. I'd like it to be entirely automated. But I cannot think of any safe ways to do this. I am not even sure that what I described would be sufficient.
Any and all insights will be appreciated.