This type of attack is used to gaining access into the victim’s website session such as email service and Facebook.Usally websites encrypted passwords when the user puts it in and sends an unencrypted session ID. This ID or the saved cookies are used by the hacker to gain access to your websites session. A plug-in that was introduced by Fire fox in 2010 called the Fire Sheep can be used to side-jacks a Wi-Fi connections are encrypted, someone nearby could easily hijack your session while you’re busy sipping coffee and browsing at the local cafe. Although SideJacking has been prevalent since 2007, the plug-in was introduced by Eric Butler. This revelation prompted much debate and discussion in Security circles and amongst bloggers. A new plug-ins was then introduced called BlackSheep, which is intended to inform the user about someone using FireSheep around them. It just makes one realize how careful one needs to be when using an unsecured public Wi-Fi at a coffee shop. Don’t think that this is restricted to laptops only; even if you are using a public Wi-Fi through your iPad or smartphone,you are equally vulnerable to the threat. This is because even in this case, a browser will be used, and the vulnerabilities lie in almost all known browsers.