If you use OpenSSH 9.6p1 both on the client and server there is no need to use this registry parameter. IGEL OS versions 12.3.1 or higher use the latest OpenSSH 9.6p1. When you use this version or newer on the peer, they will automatically use the new "strict KEX" protocol extension.
To enable Terrapin mitigation through the registry parameter:
In configuration, go toSystem > Registry > network > ssh_server > enable_terrapin_mitigation.
Enable the parameter.
ClickSaveorSave and Closeto save the change.
The following options vulnerable to Terrapin attack are disabled: