You also may be revealing the websites you visit while you use unsecured bandwidth.
This risk applies in both directions, validating the many reasons to secure wireless signals and avoid purloining your neighbor's unprotected bandwidth.
Depending on what infestation the host has picked up and how its attack vectors transfer to other systems, your supposedly innocent use of Wi-Fi bandwidth can expose you to a system-wrecking problem.
Depending on whose Wi-Fi network you access, you may wind up providing your neighbor with personally identifiable information -- your own or that of your employees, vendors or clients -- when your files and passwords become visible to the owner of the network.
To make matters worse, many wireless routers come with little or no instructions on how to set up encryption. Wireless routers with WPS built-in ship with a personal identification number (PIN – usually 8 digits) printed on them.