<a href="http://www.openssh.com/txt/release-8.3" rel="nofollow">http://www.openssh.com/txt/release-8.3</a><p>To check whether a server is using the weak ssh-rsa public key algorithm, for host authentication, try to connect to it after removing the ssh-rsa algorithm from ssh(1)'s allowed list:<p>ssh -oHostKeyAlgorithms=-ssh-rsa user@host<p>If the host key verification fails and no other supported host key types are available, the server software on that host should be upgraded.