Firewall Test – ShieldsUp

This post was written by admin on July 23, 2009
Posted Under: Free Tools, PC Security, Technology

ShieldsUp from grc.com is a very easy way to check your firewall for leaks and security, whether it be a software firewall or a hardware firewall which is built-in to many routers.

After some requests about the security of PC Tools Firewall Plus I ran the ShieldsUp test on two computers. The first has Online Armor installed which I accessed via a remote access program and the second computer has PC Tools Firewall Plus installed.

The tests are very simple and straightforward starting with 'File Sharing' to find out whether the probes can connect to the computers 'Port 139' and 'NetBios.' If the probes cannot connect to either then the computer is operating in 'stealth mode' and not exposing any of its NetBios over the internet.

The second test is to probe the 'Common Ports' and whether there is any response to pings. If there is a response then there is a loophole that hackers could easily exploit.The third test is to probe 'All Service Ports' from 0 to 1056 as these are normally the ports used for incoming connections.

If you have set your firewall correctly or configured your router correctly then all ports probed should show as stealthed unless using IM Chat clients when Port 139 will frequently show as closed (blue) rather than stealthed. This is quite normal and if you exit the IM program and clear your temporary files then retest you should find that ALL ports are stealthed.

With routers which have a built-in hardware firewall, it will scan the 'Wide Area Network' (WAN) probing for vulnerabilities.