Sun Jan 6 18:58:51 2008


Every year between Christmas and New Year's Eve, the Chaos Computer Club invites hackers and security enthusiasts to the Chaos Communication Congress in Berlin. Of course, this is a must-go event for everyone at Recurity Labs.

The event was more smooth-running than any other CCC Congress we have been to. Herding such a large number of hackers, coordinating and staying within the schedule of three tracks isn't easy. But this year, everything went perfectly well from our point of view. The community responded well to most talks we have attended and a number of follow-up activities arose, like the newly deployed barcode hackers wiki, hosted at

This year was also the first time that we could contribute the results of our research activities to the conference. We presented and released PortBunny, a specialized TCP port scanner for professional use. The motivation behind developing a new port scanner was the requirement in the professional security services world to be predictable.

Port scanning a large network can take a significant amount of time. When using the commonly available tools of the trade, the time to scan a network varies a lot, depending on how well the network is protected. But from a professional services point of view, you want to minimize the time tools work on a subject and hereby maximize the time you can work on it yourself. Additionally, being able to predict the time a TCP port scan takes is a huge improvement for estimating the overall time required for the engagement.

PortBunny is designed to run in the Linux Kernel space on dedicated machines. It uses different algorithms than most other scanners to separate the bandwidth saturation detection from the detection of filtered (aka firewalled) ports. The slides of the presentation can be found on our publications page.

PortBunny is released under the GPLv2 and can be downloaded from Any feedback is much appreciated and should be sent to

Posted by FX | Permanent link | File under: events