Not many details, and no proof of concept, which is annoying given how potentially worrisome a remotely exploitable vulnerability in a router is…
Sounds pretty bad. This is the “privileged network position” that MITM attacks are made out of.
However, given the relatively higher vulnerability exposure in countries where English is not primarily spoken, I’m a bit surprised this page is available only in English.
In the http://www.checkpoint.com/blog/fortune-cookie-hole-internet-gateway/index.html website they give some more information - but it looks like they are just trying to increase ZoneAlarm product sales.
Although the technical section does say:
Another option would be configuring your current gateway as a bridge and using a second secure device as your Internet dialer/gateway
from that page looks like you can prevent remote exploit.