I recently upgraded my mac to the latest OS only to find out that my ssh command wasn’t working. 

>ssh <strong>servername</strong>

resulted in:

> .ssh/config: line 18: Bad configuration option: useroaming
> .ssh/config: terminating, 1 bad configuration options

which looks like because I added in the following entry to my 

.ssh/config

file in response to a previous SSH vulnerability:

UseRoaming no

This vulnerability looks like it’s been fixed: https://www.solved.tips/sshconfig-line-7-bad-configuration-option-useroaming-macos-10-12-sierra/