在Ubuntu上更新SSH至最新版本，常用方法如下：
sudo apt update
sudo apt upgrade openssh-server
sudo systemctl restart ssh
ssh -V
sudo add-apt-repository ppa:openssh-team/ppa
sudo apt update
sudo apt upgrade openssh-server
sudo systemctl restart ssh
ssh -V
/etc/ssh/sshd_config）。以上步骤参考自。
