CIS101 Privacy/Security Audit - Resource Page

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Testing for Flash Cookies

Flash cookies are local data stored on your computer. This data comes from interactions with web sites that use Flash for animation and graphics. A recent research report indicated that advertisers are using Flash cookies to track consumers. This is because even if you decide to delete your browser cookies, your Flash cookies are left intact. So if your browser cookies get deleted, then some advertisers will use the Flash cookies to "re-spawn" the browser cookies.

How can you see what Flash cookies are on your machine?

There is currently no method to manage Flash cookies using either Firefox of Internet Explorer. You instead have to visit a Web page, and through that web page you have options to control your flash cookies. To view the flash cookies on your computer, click on the link below (this will open in a new window).

Flash Cookie Web Management Page (this opens in a new window)


Testing for Browser Cookies

 Cookies are small files that are stored on client machines (i.e., the machine you use for browsing) by internet servers (i.e., the machines that host and provide web pages and other internet resources). Transactions between a browser and a server often require an extended conversation. Without cookies, this conversation would not work properly. For example, when you use a web site to purchase items, your shopping cart items are stored as cookies. Another use of cookies is storing password and usernames for sites such as Facebook or your email.

Third party cookies are small data files that are stored on individual computers, but instead of being used to facilitate a transaction, they are used to track individual browsing behavior. For example, if you go to Expedia and look for flights to London, this information can be noted and used to record your interest in travel to London. Subsequently, this browsing history can be tapped to select ads for London hotels and rental cars when you browse sites like Facebook or other Web 2.0 sites. (When I went to Copenhagen for a conference last month, this happened to me.)

How can you find out what cookies are on your machine?

Directions for Firefox

If you open up Firefox, and select Tools, Options, then Privacy, you will see a window for Cookies. If you click on Show Cookies, you will see a window displaying all the cookies on your machine. To find out what these cookies are used for, use Google to search for the name.


cookie txt


For example, here is a list of cookies on my office machine. If you type “247realmedia” in to Google, you will find out that this company has programs that perform “Behavioral Targeting,” or using your browsing habits to predict what ads will be most effective. Here is the web site for 247realmedia:

For more about third party cookies go to:

Directions for Internet Explorer 7 and 8

cookie txt

  1. From the Tools menu, or the Tools drop-down at the upper right, select Internet Options.
  2. Under "Browsing History", click Settings.
  3. Click View Objects or View Files.


Internet Explorer 6.x

  1. From the Tools menu, select Options or Internet Options... .
  2. From the General tab, click Settings... .
  3. Select View Files... . You can identify your cookie files by looking beneath the "Name" or "Internet Address" column for filenames that begin with Cookie:.


Then scroll down through the temporary files to view all those that begin with “cookie”.

 cookie txt

If using Safari, refer to this link to find out how to view cookies: .

For all other browsers refer to this site: