Golden Rule #2 stressed having a NAT router–or router/firewall–between your PC and the Internet as a first line of defense. This is without question the first, most important security step, but it can be useless unless you have it properly configured; in fact, omitting one crucial first step can leave you even more vulnerable to attack that you would be without the device.
While the manufacturers try to patch such vulnerabilities, users often don’t apply the patches and even if they do, determine hackers often find other ways in. As recently as October, 2009, a blogger who stumbled across a vulnerability in more than 65,000 Time Warner Cable customer routers says the routers are still vulnerable to remote attack, despite claims by the company that it patched the routers. A report by Wired found that 45 percent of 2,729 publicly accessible Linksys routers still had a default password in place.
And that is precisely why you should put this on your list as Golden Rule #3: Always change the default user name and password of any configurable device you put on your home network.