net.schmizz.sshj.transport.TransportException: Could not verify ssh-ed25519 host key with fingerprint

[gdufeZLYL]

net.schmizz.sshj.transport.TransportException: Could not verify ssh-ed25519 host key with fingerprint
at net.schmizz.sshj.transport.KeyExchanger.verifyHost(KeyExchanger.java:210)
at net.schmizz.sshj.transport.KeyExchanger.handle(KeyExchanger.java:368)
at net.schmizz.sshj.transport.TransportImpl.handle(TransportImpl.java:517)
at net.schmizz.sshj.transport.Decoder.decodeMte(Decoder.java:159)
at net.schmizz.sshj.transport.Decoder.decode(Decoder.java:79)
at net.schmizz.sshj.transport.Decoder.received(Decoder.java:231)
at net.schmizz.sshj.transport.Reader.run(Reader.java:60)
===2020-09-24 20:36:22.566 [reader] INFO net.schmizz.sshj.transport.TransportImpl Line:205 - Disconnected - HOST_KEY_NOT_VERIFIABLE

it's wrong, how to solve, help me, thanks

[stjava]

I've got this problem, too

[sysmat]

Me to using [sshj-0.31.0.jar:0.31.0], but in cmd I could connect with ssh and known_hosts to remote server

[hpoettker]

Without more information like logs or code for a minimal example, it's very hard to give precise help. But I'll try. 😄

If host verification fails but you don't actually care about host verification, then you can turn it off by adding
sshClient.addHostKeyVerifier(new PromiscuousVerifier())
before calling SSHClient::connect.

If you care about host verification and want to use your known_hosts, make sure to call SSHClient::loadKnownHosts before connecting.

If you can connect with ssh but get the given exception with sshj, the problem is most likely that ssh and sshj negotiate different key algorithms with the remote server. Try connecting with ssh -o HostKeyAlgorithms=ssh-ed25519 user@host. If ssh warns you about conflicting host keys, remove the referenced line from known_hosts and try again. If ssh warns you that the authenticity of the remote host can't be established, proceed anyways and ssh will add the ssh-ed25519 key to your known_hosts. Afterwards, you should be able to connect with sshj without disabling host verification.

You can influence the key algorithm that sshj negotiates with the remote server with Config::setKeyAlgorithms before passing the config to the constructor of SSHClient. If you pass only the algorithm that matches the remote server's entry in known_hosts, it should work fine.

[eduveks]

The same error here with me, but as @hpoettker said before, just add this before connecting:

ssh.addHostKeyVerifier(new PromiscuousVerifier());

It was enough to solve!