If you’re concerned about using open Wi-Fi networks because of Firesheep, the highly popular new hacking tool, you should check out BlackSheep, a Firefox add-on that makes surfing on open networks safe once again.
Firesheep came onto the scene not too long ago. It’s a bit of code that allows just about anyone to access your web accounts via session hijacking. Basically, anyone browsing on a non-password-protected Internet connection, such as a Starbucks network or even an airplane, has been at risk for having their accounts accessed by a total stranger.
One way around this issue is using a VPN every time you log on via an open network. But let’s face it: For the average Internet user, this kind of work-around is a hassle, and most people care more about convenience than security.
For that reason, we’re particularly happy to see that cloud security firm Zscaler has released a simple Firefox add-on that will warn you if someone on your network is using Firesheep. That way, you can feel safe to browse the web on any network and only take extra precautions when they’re needed.
Here’s how BlackSheep works: Firesheep’s packet sniffing can’t be detected, but what can be detected is Firesheep’s requests to websites like Facebook using your cookies. BlackSheep detects this type of activity by making requests to random sites known to FireSheep every five minutes (you can adjust the timing) with fake values.
If anyone else on the network starts using those same fake values to make requests, then BlackSheep knows someone on the network is using Firesheep, and you get a warning in your current browser tab.
BlackSheep was based on Firesheep’s code to ensure its effectiveness. In a word, for every hack, there is an equal and opposite counter-hack.
You can get BlackSheep for Firefox free from Zscaler. Here’s a quick demo of how the add-on works: