Firesheep and Blacksheep

FireSheep – A Firefox extension that demonstrates HTTP session hijacking attacks.

Firesheep allowed any user to seamlessly hijack the web session of another user on the same local network. Although such attacks are not new, the ease of use presented by Firesheep brought session hijacking to the masses.

BlackSheep - A Tool to Detect Firesheep

BlackSheep is a Firefox plugin that is designed to combat Firesheep. BlackSheep does this by dropping ‘fake’ session ID information on the wire and then monitors traffic to see if it has been hijacked. While Firesheep is largely passive, once it identifies session information for a targeted domain, it then makes a subsequent request to that same domain, using the hijacked session information in order to obtain the name of the hijacked user along with an image of the person, if available. It is this request that BlackSheep identifies in order to detect the presence of Firesheep on the network. When identified, the user will be receive the following warning message:

http://www.zscaler.com/blacksheep.html