Free tools are appearing to help users defend themselves against Firesheep, a plug-in for Firefox that allows attackers to hijack your web sessions. BlackSheep works by making HTTP requests using fake variables to the websites watched by the tool. Another workaround is HTTPS Everywhere, forcing websites to SSL-encrypt every page. The goal of releasing it was to expose the lack of security inherent to using unencrypted Wi-Fi networks, says its creator. The necessary packet-sniffing tools, including NetStumbler and Kismet, have been available for years.”]
Source: https://www.darkreading.com/attacks-breaches/tools-gut-firesheep-cookie-hijacking-attack