Most internet browsers cache what site you last visited and offers that information to the next site you go to. It is called an HTTP Referrer. This information is used for website statistics and demographics. This information could potentially be used for nefarious reasons. The company GRC makes the well known Spinrite hard disk recovery software and security software. According to their site:
“The web’s HTTP protocol was designed with little concern for a web surfer’s privacy and well before aggressive commercial interests decided to track surfers across the web, while storing and compiling any personal information that might leak from their browser.
Information is leaking from web browsers?
Yes, absolutely, and frighteningly so. The often repeated claims that “no user identifiable information is being sent or collected” is just so much nonsense. Those statements are meant to lull trusting and uninformed Internet users into a false sense of privacy and security.
When a web resource is requested from a server, the “Referer” header line provides the requested server with the URL of the web page that requested the item. But if an online web form has just been filled out and submitted using the most common “GET” method, the web surfer’s potentially personal and private data will appear in the URL and it will be sent to any third-party servers, such as advertising, tracking, or web-bug servers, whose resources appear on the form’s submission confirmation page!”
Now some browsers, like Internet Explorer, are supposed to block this HTTP Referrer when you leave a secure site and go to a none secure website, but not all browsers do. Also, your IP address is given to websites so they can track demographics. If you are not using a proxy, firewall or internet security software, this could point directly back to your individual machine. While you are at GRC, it is also a great place to check and see if you have any open ports on your system. Their Shields Up! online program checks to see if your firewall is doing its job and blocking access to your computer. The best you can get is a “True Stealth” rating, which means that your firewall doesn’t give your computer away by responding to general ping or probing requests. If you have open ports, you should check into it.
Daniel W. Dieterle