sshd version that ships with Ubuntu 22.04
seems to have abandoned RSA authentication. Well, that’s not true. It’s about the hash algorithm used by the “old” protocol by the name
ssh-rsa, which is deemed insecure by today’s standards. RSA is alive and kicking inside the protocols going by the names
Anyway, the solution was to enable a protocol on the server side (in my case a VM) that was understood by the client, i.e. SpeedCommander. Thus I added in
sshd and was happily churning on.
PS: I have no qualms about the use case, because it’s a VM to which I locally connect. For other use cases I would probably resort to other solutions. But then: my main system at home runs Linux, not Windows 😉