Those attacks are still "gentle" as if you have (and you should) a read only backup you can resolve it with near 0 dataloss. What I fear are cancer like virus,

Those attacks are still "gentle" as if you have (and you should) a read only backup you can resolve it with near 0 dataloss. What I fear are cancer like virus, not wiping or encrypting data at time T, but introducing subtle errors on a longer period. You would be contacted by hackers saying your last 6 months of data contain error. That's scary.