Important note for future FreeBSD base system OpenSSH update

[Eugene Grosbein]

10.09.2021 1:01, Ed Maste wrote:

> To check whether a server is using the weak ssh-rsa public key
> algorithm, for host authentication, try to connect to it after
> removing the ssh-rsa algorithm from ssh(1)'s allowed list:
> 
>     ssh -oHostKeyAlgorithms=-ssh-rsa user at host
> 
> If the host key verification fails and no other supported host key
> types are available, the server software on that host should be
> upgraded.

I have some telco equipment (E1/SS7) based on custom Linux distro built by a vendor:

$ ssh -oHostKeyAlgorithms=-ssh-rsa user at host
Unable to negotiate with X.X.X.X port 22: no matching host key type found. Their offer: ssh-rsa

I've already asked the vendor for possible upgrade and was told that no upgrade will be available.

Will I be able to use ssh_config and following command to re-enable the feature after planned import?

HostKeyAlgorithms ssh-rsa