Tooling Around with NMap v5

Okay, I'll admit - I'm easily amused by the shiny and the new. Especially if it allows me to better poke and prod around in the musty, dusty corridors of networks. Better still if I can have some fun while doing it. NMap v5 appears to be all of those things for me. Released just today, I'm already enjoying the new features.

For those who don't know, NMap is a network scanning tool. It is used for (among other things) finding computers (or hosts), seeing what services they might be offering up to the rest of the world and generally finding out all sorts of potentially useful and interesting tidbits.

Among the many new features are two really nice utilities. The first is Ncat, a rewrite of the very useful Netcat tool. Netcat is known as the network Swiss Army Knife because of its versatility. Ncat seems to meet this standard and even improve upon it. It can act as a proxy, redirecting network traffic; be used to interact with or pretend to be services like web servers or telnet; can connect multiple computers together, using encrypted channels; and much, much more of interest to any network spelunker.

The second addition is the Ndiff utility. Ndiff makes it easy to compare multiple scan results and report any differences. Imagine running several scans of a network and trying to compare results to see what's changed. With just a few hosts, this isn't too difficult. Now try this for hundreds or even thousands of results. Ndiff simplifies the task by performing the grunt work for you and generates a list of changes in hosts, services, etc. Previously Ndiff existed as a separate Python program; now it is included as part of the NMap suite. Very nice.

I've also been tinkering with the latest version of ZenMap, a bundled Windows GUI for NMap. There are some nice eye candy features included, with the most interesting so far being the impoved network diagramming function. This offers a view of scan results by hostname, IP address, even service. Again, really interesting stuff if you're plumbing out a network.

This is just scratching the surface of what Nmap v5 offers. If you've used any previous version of NMap, don't hesitate - go get v5! If you've never used NMap before, but are wondering what all this network scanning fuss is, v5 makes it easy to get your feet wet. Highly recommended.