Friday, February 1, 2008

Ever heard of Flash cookies?

Have you ever gone to the trouble of deleting all your Internet temporary files, cookies, browsing history and so on, then rebooting only to find that a web site still knows who you are? For a long time it really puzzled me how this particular web site still knew who I was after killing what I thought was every piece of identifying material on my PC.
Turns out that Adobe Flash can also be used to store cookies, unsurprisingly these are known as 'Flash Cookies'. As you can see from the image below this is how the sites were still able to track me.

When I looked through the list of sites that had stored Flash Cookies on my system I found quite a variety including those typically from people like Doubleclick whose 'third party cookies' allow your browsing machine (and people who use it) to be tracked across different web sites. So, it is possible that if you go two different web sites with 'third party cookies', people like Doubleclick know where you've been and can thus start to profile you. The more you browse the more 'third party cookies' you get and the better the profile that is constructed about you. This profile allows advertisers to direct certain banners at you (ah ha you say, so that is why the ad seem to 'know' me) as well as sell your browsing habits to marketing companies. That is why many normal 'third party cookies' are considered spyware, because they track your activity WITHOUT your consent!
So even if your turn off or reject normal cookies these Flash cookies can still be recorded on your system allowing you to be profiled. Now, that you know about flash cookies you may well ask where on my PC can I go to turn them off? Ah ha, another gotcha - there is no setting on your PC (that I found anyway). You have to go to a page on the Adobe web site (Abode are the owners of Flash), which will query the settings on your system and allow you to make machines and present you with the control panel you see in the above picture.
As with normal cookies, disabling or deleting Flash cookies may prevent some sites from working correctly so beware. However, now that you at least know how to change the settings you can always return and adjust your settings to allow only what you deem necessary. So all you need now is the Adobe web site where you make these changes and here it is :
http://www.macromedia.com/support/documentation/en/flashplayer/help/settings_manager.html
Clearly many sites are using whatever means they can to record information about you so they can profile you. To me, if they didn't ask, that is an invasion of my privacy. I am only happy for the SITES I WANT to profile me but NO OTHERS. Heaven knows how many other avenues are out there that companies are using to track web surfers but at least now you know how to control this one.
PS I'd also make sure your select the option to TURN OFF unrestricted access to your microphone and camera. Why the hell this should ever be on by default beats the hell out of me.