14 DAY TRIAL // Adobe has been working with browser vendors to develop a way of deleting Flash Player local shared objects (LSO), also known as Flash cookies, directly from the browsers.
Local shared objects are part of the local storage feature that rich Internet applications (RIA) can use to store various settings or cached items.
This allows, for example, a Web video player to restore the last volume setting or load the last playlist automatically when the user returns to the page.
However, security researchers have warned since several years ago that local storage can potentially be abused for user tracking purposes.
Flash LSOs, in particular, can be used to re-spawn tracking cookies. For example, a website can store an unique identifier in both a plain text cookie and a LSO.
If the user deletes the cookie through the browser controls and revisits the website, the ID can be read from the LSO used to recreate the cookie.
There are currently several lawsuits seeking class action status against large companies like Disney, Warner Bros. Records, or Ustream, for using this exact method to track visitors across their websites.
Even though Adobe condemned the practice since the very beginning, the company was strongly criticized for the obscurity of LSO management controls.
The Flash Settings Manager which can be used to delete them, can only be accessed by visiting a special page on the macromedia.com website, an unusual way for a local application.
Because of this, Adobe has been working with Google and Mozilla to develop a new application programming interface (API) called "NPAPI ClearSiteData" which will allow browsers to interact with plugins to clear local storage data.
It looks like Chrome will be the first browser to implement the new API and Firefox will follow. Adobe will support it in upcoming versions of Flash Player and other browser and plugin developers can add it too.
The company is also working on a local version of the Flash Player Settings Manager. "[...] We’ll enable you to access the Flash Player Settings Manager directly from your computer’s Control Panels or System Preferences on Windows, Mac and Linux, so that they’re even easier to locate and use," announces Flash Player Group product manager, Emmy Huang.