Based on my quick look at ZyXEL's SSH service I see that all of the processes that you could run on the system via SSH were guarded by SELinux. This means that the system did not allow specific processes to be executed without the advocation of a SELinux user currently logged into the system. So, a malicious user cannot execute the SSH daemon process without an SELinux user executing it. However, this is based off of your package build here which I do not have access to. I would recommend contacting ZyXEL support in order to get policy and guidance on the best way to proceed.
Though the page claims that the switch has ethernet, I cannot see anything that indicates such a connection (FWIFW). The spec sheet mentions LAN port, but then the page doesn't mention switch in any form, it just says Jumper cables and how to connect them to the QEW port and the LAN port. The spec sheet also references the product's use as a NAS, but again no mention of a switch (FWIFW). The PDF advertised on the official page that the zyns1600 has a connector that allows plus and minus values of power to be applied as the (+) and (-) port on the port. In that case, no Ethernet would be necessary as only power would be supplied to the cable. The cable that I have been testing might or might not have any Ethernet port on the end of it. d2c66b5586