A guided tour to someone else's network
Breaking In

© Konstantinos Kokkinis, 123RF
You need to think like an attacker to keep your network safe. We asked security columnist Kurt Seifried for an inside look at the art of intrusion.
In June 2009, a virtualization product aimed at web servers was found to have a few security vulnerabilities. The end result was that about 100,000 web sites got hacked and deleted at a number of different providers. (It's not clear how many were recovered.) Also in June, the security-related website astalavista.com was hacked, and a variety of files and databases, as well as the remote backups, were deleted. These were only the "big" hacks that were newsworthy, the actual number of websites and servers compromised is much higher.
The techniques for network attacks keep evolving. In this article, I take a look at some favorite strategies for the latest generation of intruders.
A Quick Legal Disclaimer
Please note that engaging in the kinds of activities described in this article can potentially get you into trouble, ranging from a stern talking to by your network administrator to a less-than-enjoyable, all-expenses-paid vacation courtesy of whichever law enforcement agency you manage to annoy the most. So why am I writing this? If you want to build and maintain secure systems, you need to understand how to make them fail. If you want to buy a good lock, you either have to buy a bunch of locks and learn how they work or find someone who has [1]. My advice is to get a cheap quad-core machine with lots of RAM, put VirtualBox or VMware on it, and build systems and networks you can attack without disturbing anyone else.
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