This report by Ars Technica should worry everyone. It describes a new vulnerability of SSH.

SSH, or Secure Shell Protocol, was invented in 1995, and provides secure access to remote computers. It provides not only command-line remote access, but also remote graphical applications (where the program runs on the remote computer and any windows that it opens appear on the local computer) using a feature called X11 forwarding.

This may seem rather esoteric to some readers, but it is the basis of the administration of remote computer systems like web-servers and cloud servers. It is very powerful and easy to use, and until now has been considered impregnably secure.

Now, however, it has been found to be vulnerable to a so-called "man in the middle" attack. We should expect a series of system penetration events, resulting in hackers gaining access to Internet-connected systems and stealing valuable data, ransomware attacks and the like.

Luckily, I do not use SSH to access my servers while away from home. Instead, I have written some tools which allow me to do most of the system administration by other methods.