In this guide, we will show you the steps to fix the issue of SSH not working in macOS Ventura. Secure Shell is an encrypted/cryptographic network protocol that enables two computers to communicate and share data over the servers. Since the communication is encrypted, it is the preferred mode, especially on insecure networks. When it comes to Apple’s underlying OS, it already features a built-in SSH client [Terminal].

It is based on a client-server architecture and allows you to connect an SSH client instance with an SSH server. However, as of late, it is giving out a tough time to the users on the latest macOS. According to the affected users, SSH is not working in macOS Ventura. As a result, they are unable to log in to their Mac running Ventura from devices with deprecated keys. Apart from that, some are also getting the “no matching host key type found” error. So why is this happening?

One reason could be the fact that Ventura comes with OpenSSH_9.0p1 and “This release disables RSA signatures using the SHA-1 hash algorithm by default”. So how to fix this issue? Well, advanced users could opt for the technical route of generating keys based on a more secure hash algorithm. On the other hand, beginners could make use of the nifty workaround that we shared below. Follow along.

  1. Open the ~/.ssh/ssh_config file in a text editor
  2. Add the following lines to the end of the file:
HostkeyAlgorithms +ssh-rsa
PubkeyAcceptedAlgorithms +ssh-rsa
  1. You're all set.

Original source: https://www.droidwin.com/ssh-not-working-in-macos-ventura-fix/