As you all know, cookie enables websites owners to track visitor activities and can use these data for legal or illegal purposes. Currently, there’re mainly three forms of cookies - standard cookie, Flash cookie (Local Shared Objects or LSOs), and the newest Evercookie. Standard and Flash cookies are easy to remove, but Evercookie is more persistent and difficult to remove, because it sores cookie data in multiple places.

Furthermore, it can rebuild the cookie, if you removed it from your computer, unless you have removed them from all locations and reset the local storage. So, even if you have deleted the standard and flash cookies, Evercookie implemented website can still identify you.

According to the developer,

“Evercookie is a JavaScript API that produces extremely persistent cookies in a browser…… Evercookie accomplishes this by storing the cookie data in several types of storage mechanisms that are available on the local browser”.

It stores data in:

1. Standard HTTP Cookies
2. Local Shared Objects (Flash Cookies)
3. Silverlight Isolated Storage
4. Storing cookies in RGB values of auto-generated, force-cached PNGs using HTML5 Canvas tag to read pixels (cookies) back out
5. Storing cookies in Web History
6. Storing cookies in HTTP ETags
7. Storing cookies in Web cache
8. window.name caching
9. Internet Explorer userData storage
10. HTML5 Session Storage
11. HTML5 Local Storage
12. HTML5 Global Storage
13. HTML5 Database Storage via SQLite

Here I am talking about a plug-in for Firefox called ‘Anonymizer Nevercookie’. Its developer claims that it can prevent Evercookie from storing data in the browser. It does this by creating a new profile for the Firefox’s private browsing mode and removes Evercookie from all locations after the browsing session.

If you’re concerned more about your privacy, you can try this plug-in from here. After installing the plug-in, launch the Firefox browser and go to Tools - Start Private Browsing.

A new browser window will open. It will be branded with a blue Navigation Menu bar. Use this window for your private browsing session. To leave private browsing mode, close the private browsing window in the parent Firefox window, go to Tools - Stop Private Browsing.

More details and download available here (via)