Steps to disable SSH CBC Mode Ciphers on port 2222 in Red Hat Virtualization Manager

Issue

• ovirt-vmconsole enables secure access to virtual machine serial console. It uses SSH protocol to tunnel the console from customer to destination host.
• When nmap utility is being run on port 2222 following CBC Mode Ciphers are seen enabled.

# nmap --script ssh2-enum-algos -sV -p 2222 manager.example.com

Starting Nmap 6.40 ( http://nmap.org ) at 2021-07-09 13:44 EDT
Nmap scan report for manager.example.com (10.x.x.x)
Host is up (0.000088s latency).
PORT     STATE SERVICE VERSION
2222/tcp open  ssh     OpenSSH 7.4 (protocol 2.0)
...
|   encryption_algorithms (12)
|       chacha20-poly1305@openssh.com
|       aes128-ctr
|       aes192-ctr
|       aes256-ctr
|       aes128-gcm@openssh.com
|       aes256-gcm@openssh.com
|       aes128-cbc
|       aes192-cbc
|       aes256-cbc
|       blowfish-cbc
|       cast128-cbc
|       3des-cbc