> You're only safe if you have offsite backups with drives that didn't mount to your computer recently.
Or if your backup solution is—from the perspective of the computer being backed up—an append-only store. Like a box of tapes, or Tarsnap using restricted keys, or Arq pointed at a versioned S3 bucket, or a NAS exposing an iSCSI target backed by an LVM thin pool LV with automatic daily snapshots.
Sadly, as far as I know, no turn-key hardware "home backup" or "home NAS" product is in that category, though.
Or if your backup solution is—from the perspective of the computer being backed up—an append-only store. Like a box of tapes, or Tarsnap using restricted keys, or Arq pointed at a versioned S3 bucket, or a NAS exposing an iSCSI target backed by an LVM thin pool LV with automatic daily snapshots.
Sadly, as far as I know, no turn-key hardware "home backup" or "home NAS" product is in that category, though.