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New Cloud-Based Wireless Password Cracker

Security reports have consistently pointed out weak or default passwords as a major source for data breaches, similar to the recent Verizon Data Breach Study. Now there's a new service that tests the strength of passwords used in the encryption of wireless access points.
Security reports have consistently pointed out weak or default passwords as a major source for data breaches, similar to the recent Verizon Data Breach Study. Now there's a new service that tests the strength of passwords used in the encryption of wireless access points.

Researcher Moxie Marlinspike launched the service, which runs on a cluster of hundreds of servers to speed up the attack against the WPA encryption algorithm, and is hosted at www.wpacracker.com. To test the service, I captured a small number of packets on my home network and uploaded them, to be checked against 135 million different passwords. I then paid a fee of $17 to select the 200-node cluster and was informed that the cracking process would take roughly 40 minutes. Soon I got a message from the system informing me that my packet file was queued for service:

Subject: WPA Cracker Payment Received [my SSID was here]
[email protected] to me -11:32 PM (8 hours ago)
This email is to notify you that wpacracker.com has successfully received your Amazon payment. Your job is now being added to the cracking queue. There are 0 jobs ahead of yours.
Almost one hour later, the result:

Subject: WPA Cracker Results [my SSID was here]
[email protected] to me - 12:27 AM (7 hours ago)
WPA Cracker has completed its dictionary attack against your WPA handshake. We exhausted our entire 135 million word dictionary without finding a matching PSK for the handshake you submitted. This run took 3269 seconds. Thank you for using wpacracker.com, this concludes your job.
The cluster was not able to crack my password -- good for my password strength, but a bit disappointing because I would have really liked to see the results of a successful run. Overall, I think WPAcracker is a useful tool and a very pragmatic implementation using cloud computing. Moxie is using a IaaS (infrastructure-as-a-service) company in the underlying implementation of the cluster. The IP address for www.wpacracker.com points to Linode.com. This is cloud computing at its best, enabling organizations of any size to leverage hundreds or even thousands of machines on demand and to harness their computing power at a cost that anybody can afford.

P.S.: I used aircrack-ng included in the Backtrack v3 distro on my Eee PC -- here is a good step-by-step guide to the setup.

-- As the CTO for Qualys, Wolfgang Kandek is responsible for product direction and all operational aspects of the QualysGuard platform and its infrastructure. Wolfgang has more than 20 years of experience in developing and managing information systems. His focus has been on Unix-based server architectures and application delivery through the Internet. Wolfgang provides the latest commentary on his blog: laws.qualys.com and also publishes his Patch Tuesday commentary to the QualysGuard channel: www.youtube.com/QualysGuard. He is a frequent source in business and trade media and speaks at industry conferences around the world, most recently at RSA 2009.

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