I wonder about:

- silently compromised systems, active but unknown

- VPS provider doing security behind your back

I'd be worried about this too. Like there must be AI bots that "try the doors" on known exploits all over the internet, and once inside just do nothing but take a look around and give themselves access for the future. Maybe they become a botnet someday, but maybe the agent never saw the server doing anything of value worth waking up its master for— running a crypto wallet, a shard of a database with a "payments" table, an instance of a password manager like Vault, or who knows what else might get flagged as interesting.