Ubuntu upgrade some old package from old release – such as SSH

Upgrade the version:

sudo apt-add-repository 'deb http://archive.ubuntu.com/ubuntu yakkety main universe multiverse'
sudo apt-get update
sudo apt-get install openssh-server=1:7.3p1-1

or we can install from source:

wget http://mirror.exonetric.net/pub/OpenBSD/OpenSSH/portable/openssh-7.2p2.tar.gz
tar -zxvf openssh-7.2p2.tar.gz
cd openssh-7.2p2
./configure
make
sudo make install