This week, over on the newly started An Eye on Surveillance blog, the first in a series of posts about egregious privacy intrusions -- Snooping Browsing History through HTML:
Unless you have installed a couple of specific firefox extensions to protect yourself, the owners of any website you visit can tell whether you have visited any other website.
It has been known since 2006 that is it possible for any website to query whether you have visited any of a list of other websites without even having to use javascript. One way to do this is to rely on the fact that CSS (that language for HTML style sheets used by virtually every website) allows website hosts to specific a different color or background image for a given link depending on whether that link has been visited before. CONTINUED...
Stay tuned to An Eye on Surveillance for more on general privacy vulnerabilities, as well as specific cases such as the British police's portable fingerprint readers.