Multiple networks
Advanced network environments often employ mutliple IP subnets, e.g. to separate wireless hosts from the rest of the network. However, when connected to such an environment, La Fonera fails to setup her firewall rules: Although the device does protect the network it is directly connected to, it fails to shield other local networks from any foreign Fonero using the public signal. La Fonera does not know about other local networks, and therefore treats them as part of the public internet.

To resolve this issue, consider gaining root access to your Fonera. After that, manually add firewall rules to the file /etc/firewall.user
in order to prevent Foneros from accessing your local network.
La Fonera: Bugs and Flaws