It's not totally clear but I think this only affects NAS boxes and not routers.
Stuart
It does list model numbers and they all start NAS/NSA so yeah I think its fairly clear.
You gotta love Capitalism:
many of these devices are no longer supported by Zyxel and will not be patched
Its about time vendors were forced to fix security flaws regardless of how old the product is. Surely it can be argued a flaw like this means the product never was fit for purpose thus should absolutely be patched regardless of its age?